what is the standard deviation of 2,3,6,9,10

Answer: Option 'A' is correct.

Step-by-step explanation:

Since we have given a situation that

If an increase in one variable causes a decrease in another​ variable,

Then, there is inverse relationship.

When one variable is increased whereas other variable falls.

There will be inverse relationship.

Since inverse relation has negative relation.

Then, there is a negative relationship.

Hence, Option 'A' is correct.

An increase in one variable causing a decrease in another indicates a negative relationship between the two variables, characterized by opposite directional movements and graphically represented by a line with a negative slope.

When discussing the correlation between two variables, it is important to consider the direction and type of relationship they share. If an increase in one variable causes a decrease in the other variable, this is defined as a negative relationship. In a negative relationship, the two variables move in opposite directions, meaning that as one variable increases, the other decreases and vice versa.

The relationship is depicted graphically as a line with a negative slope on a graph, where the line descends as it moves from left to right. This situation should not be confused with dependent, direct, or independent relationships, which describe different aspects of variable interaction.

Answer:

The equation of the circle is (x + 10)² + (y + 5)² = 125 in standard form

Step-by-step explanation:

* lets study the standard form of the equation of a circle

- If the coordinates of the center of the circle are(h , k) and its radius

 is r, then the standard equation of the circle is:

 (x - h)² + (y - k)² = r²

* Now lets solve the problem

∵ The coordinates of the center of the circle are (-10 , -5)

∵ The standard form of the equation is (x - h)² + (y - k)² = r²

∵ h , k are the coordinates of the center

∴ h = -10 , k = -5

∴ The equation of the circle = (x - -10)² + (y - -5)² = r²

∴ The equation of the circle = (x + 10)² + (y + 5)² = r²

- To find the value of the radius lets use the point (-5 , 5) to

  substitute their coordinate instead of x and y in the equation

∵ The circle passes through point (-5 , 5)

∵ (x + 10)² + (y + 5)² = r²

- Use x = -5 and y = 5

∴ (-5 + 10)² + (5 + 5)² = r² ⇒ simplify

∴ (5)² + (10)² = r²

∴ 25 + 100 = r²

∴ r² = 125

* Now lets write the equation in standard form

∴ (x + 10)² + (y + 5)² = 125

* The equation of the circle is (x + 10)² + (y + 5)² = 125 in standard form

Answer:

Type of function: Absolute Value

Transformations: 1) elongated by a stretch factor of 2; 2) shifted left 3; 3) shifted down 5

Answer:

Step-by-step explanation:

The parent function is

[tex]f(x)=|x|[/tex]

The transformed function is

[tex]g(x)=2|x+3|-5[/tex]

You can deduct by comparison, that the function was shifted 5 units down, 3 units to the left, and vertically streched by a scale of 2.

We deduct this transfromations based on the following rules.

[tex]f(x)-u[/tex] indicates a movement downside [tex]u[/tex] units.

[tex]f(x+u)[/tex] indicates a movement leftside [tex]u[/tex] units.

[tex]uf(x)[/tex] indicates a vertical stretch for [tex]u>1[/tex].

Step-by-step answer:

Given:

mean, mu = 200 m

standard deviation, sigma = 30 m

sample size, N = 5

Maximum deviation for no damage, D = 100 m

Solution:

Z-score for maximum deviation

= (D-mu)/sigma

= (100-200)/30

= -10/3

From normal distribution tables, the probability of right tail with

Z= - 10/3

is 0.9995709, which represents the probability that the parachute will open at 100m or more.

Thus, by the multiplication rule, the probability that all five parachutes will ALL open at 100m or more is the product of the individual probabilities, i.e.

P(all five safe) = 0.9995709^5 = 0.9978565

So there is an approximately 1-0.9978565 = 0.214% probability that at least one of the five parachutes will open below 100m

The probability that at least one out of five parachutes causes equipment damage, given that the parachute opening altitude is normally distributed with a mean of 200m and standard deviation of 30m, is approximately 0.2%.

The situation described is a question of probability related to the normal distribution. In this case, we are asked to find the probability of a parachute opening at less than 100m, which will cause damage. First, we need to standardize the value to a z-score. The z-score is calculated by subtracting the mean from the value of interest and dividing by the standard deviation. In this case, it will be (100-200)/30, which equals to about -3.33.

By looking at a z-table or using a statistical calculator we find that the probability of single parachute causing damage is approximately 0.0004. However, the question is interested in the probability of at least one out of five parachutes causing damage. This can be approached as 1 minus the probability of none of the five causing damage, which will be 1 - (1-0.0004)^5. Thus, the resulting probability of equipment damage to the payload of at least one of five independently dropped parachutes is approximately 0.002 or 0.2%.

https://brainly.com/question/31321305

#SPJ2

Answer:

[tex]\large\boxed{7.\ B.\ 8s^2+16s+1}\\\\\boxed{8.\ D.\ -15t^9u^{11}}\\\\\boxed{11.\ C.\ 3,\ -2}[/tex]

Step-by-step explanation:

[tex]7.\\(3s^2+7s+2)+(5s^2+9s-1)=3s^2+7s+2+5s^2+9s-1\\\\\text{combine like terms}\\\\=(3s^2+5s^2)+(7s+9s)+(2-1)\\\\=8s^2+16s+1[/tex]

[tex]8.\\(-3t^2u^3)(5t^7u^8)=(-3\cdot5)(t^2t^7)(u^3u^8)\qquad\text{use}\ a^na^m=a^{n+m}\\\\=-15t^{2+7}u^{3+8}=-15t^9u^{11}[/tex]

[tex]11.\\n-the\ number\\\\n^2=n+6\qquad\text{subtract}\ n\ \text{and}\ 6\ \text{from both sides}\\\\n^2-n-6=0\\\\n^2+2n-3n-6=0\\\\n(n+2)-3(n+2)=0\\\\(n+2)(n-3)=0\iff n+2=0\ \vee\ n-3=0\\\\n+2=0\qquad\text{subtract 2 from both sides}\\n=-2\\\\n-3=0\qquad\text{add 3 to both sides}\\n=3[/tex]

Answer: The required proportion is [tex]\dfrac{172}{523}[/tex] in fraction and [tex]0.329[/tex] in decimals.

Step-by-step explanation:

Since we have given that

Number of suspected criminals is drawn = 523

Number of criminals were captured = 172

We need to find the proportion of people who were caught after being on the 10 Most wanted list.

So, Proportion of people who were caught is given by

[tex]\dfrac{172}{523}\\\\=0.3288\\\\\approx 0.329[/tex]

Hence, the required proportion is [tex]\dfrac{172}{523}[/tex] in fraction and [tex]0.329[/tex] in decimals.

The estimated proportion of suspected criminals caught after being on the FBI's 10 Most Wanted list is 0.329, or 32.9%, based on a sample where 172 out of 523 individuals were captured.

To estimate the proportion of people who were caught after being on the FBI's 10 Most Wanted list, we can use the sample data provided. In the sample, 523 suspected criminals were monitored and 172 were captured. The estimated proportion of individuals caught is calculated by dividing the number of people captured by the total number in the sample.

To find this proportion, we perform the following calculation:

Proportion = Number of people captured / Total number of suspected criminals

Proportion = 172 / 523

Proportion = 0.329 (rounded to three decimal places)

So, the estimated proportion of people who were caught after appearing on the list is approximately 0.329, or 32.9%.

ANSWER

The relation is not a function.

EXPLANATION

The relation is not a function because we have an x-coordinate mapping on to more than one y-coordinate.

This occurs at x=1.

The ordered pairs (1,1) and (1,3) disqualify the relation from being a function.

Hence the relation is not a function.

Answer:

27 SUVs

Step-by-step explanation:

Let number of ordinary cars be x and SUVs be y

We can write 2 equations and use substitution to solve for the number of SUVs.

"The number of ordinary cars is larger than the number of sport utility vehicles by 59.3%"-

This means that 1.593 times more is ordinary cars (x) than SUVs (y), so we can write:

x  = 1.593y

"The difference between the number of cars and the number of SUVs is 16" -

Since we know ordinary cars are "more", we can say x - y = 16

We can now plug in 1.593 y into x of the 2nd equation and solve for y:

x - y = 16

1.593y - y = 16

0.593y = 16

y = 27 (rounded)

Hence, there are 27 SUVs

Answer:

[tex]F_{yx}=3x^{2} cos(xy)- yx^{3} sin(xy)[/tex]

Step-by-step explanation:

We need to find out the partial differential [tex]F_{yx}[/tex] of [tex]F(x,y)=x^{2}sin(xy)[/tex]

First, differentiate [tex]F(x,y)=x^{2}sin(xy)[/tex] both the sides with respect to 'y'

[tex]\frac{d}{dy}F(x,y)=\frac{d}{dy}x^{2}sin(xy)[/tex]

Since, [tex]\frac{d}{dt}\sin t =\cos t[/tex]

[tex]\frac{d}{dy}F(x,y)=x^{2}cos(xy)\times \frac{d}{dy}(xy)[/tex]

[tex]\frac{d}{dy}F(x,y)=x^{2}cos(xy)\times x[/tex]

[tex]\frac{d}{dy}F(x,y)=x^{3}cos(xy)[/tex]

so, [tex]F_y=x^{3}cos(xy)[/tex]

Now, differentiate above both the sides with respect to 'x'

[tex]F_{yx}=\frac{d}{dx}x^{3}cos(xy)[/tex]

Chain rule of differentiation: [tex]D(fg)=f'g + fg'[/tex]

[tex]F_{yx}=cos(xy) \frac{d}{dx}x^{3} + x^{3} \frac{d}{dx}cos(xy)[/tex]

Since, [tex] \frac{d}{dx}x^{m} =mx^{m-1}[/tex] and [tex] \frac{d}{dt} cost =-\sin t[/tex]

[tex]F_{yx}=cos(xy)\times 3x^{2} - x^{3} sin(xy)\times \frac{d}{dx}(xy)[/tex]

[tex]F_{yx}=cos(xy)\times 3x^{2} - x^{3} sin(xy)\times y[/tex]

[tex]F_{yx}=3x^{2} cos(xy)- yx^{3} sin(xy)[/tex]

hence, [tex]F_{yx}=3x^{2} cos(xy)- yx^{3} sin(xy)[/tex]

Answer:

12m

Step-by-step explanation:

We are given the following expression where a fraction is divided by another fraction:

[tex]\frac{\frac{16m^2}{m^2+5} }{\frac{4m}{3m^2+15} }[/tex]

To change this division into multiplication, we will take reciprocal of the fraction in the denominator and then solve:

[tex] \frac { 1 6 m ^ 2 } { m^2+5} } \times \frac{3m^2+15}{4m}[/tex]

Factorizing the terms to simplify:

[tex] \frac { 4 m ( 4m ) } { m ^ 2 + 5 } \times \frac { 3 ( m ^ 2 + 5 ) } { 4 m } [/tex]

Cancelling the like terms to get:

12m

Answer: [tex]12m[/tex]

Step-by-step explanation:

Given the expression [tex]\frac{\frac{16m^2}{m+5}}{\frac{4m}{3m^2+15}}[/tex], we can rewrite it in this form:

[tex](\frac{16m^2}{m+5})(\frac{3m^2+15}{4m})[/tex]

Now we must multiply the numerator of the first fraction by the numerator of the second fraction and   the denominator of the first fraction by the denominator of the second fraction:

 [tex]=\frac{(16m^2)(3m^2+15)}{(m^2+5)(4m)}}[/tex]

According to the Quotient of powers property:

[tex]\frac{a^m}{a^n}=a^{(m-n)}[/tex]

And the Product of powers property states that:

[tex](a^m)(a^n)=a^{(m+n)}[/tex]

Then, simplifying, we get:

[tex]=\frac{3(m^2+5)(4m)(4m)}{(m^2+5)(4m)}}\\\\=3(4m)\\\\=12m[/tex]

[tex]|\Omega|=52\cdot51\cdot50=132600[/tex]

a)

[tex]|A|=4\cdot3\cdot2=24\\P(A)=\dfrac{24}{132600}=\dfrac{1}{5525}[/tex]

b)

[tex]|A|=13\cdot12\cdot11=1716\\P(A)=\dfrac{1716}{132600}=\dfrac{11}{850}[/tex]

a. Probability of all 3 cards being queens:

b. Probability of all 3 cards being spades:

Answer: [tex]\dfrac{1}{6}[/tex]

Step-by-step explanation:

The given event : A randomly drawn marble is blue.

The number of blue marbles in the bag = 2

The total number of marbles in the bag = [tex]2+7+3=12[/tex]

Now, the probability of drawing a blue marble is given by  :-

[tex]\text{P(Blue)}=\dfrac{\text{Number of blue marbles}}{\text{Total number of marbles}}\\\\\Rightarrow\text{P(Blue)}=\dfrac{2}{12}=\dfrac{1}{6}[/tex]

Hence, the probability of the given event event = [tex]\dfrac{1}{6}[/tex]

Answer:

  3x -4y = 2

Step-by-step explanation:

A plot of the points makes it clear that the longest diagonal is BD. The 2-point form of the line through those points can be found by filling in ...

  y = (y2 -y1)/(x2 -x1)(x -x1) +y1

  y = (4 -(-2))/(6 -(-2))(x -(-2)) +(-2) . . . . . fill in points B and D

  y = (6/8)(x +2) -2

  4y = 3(x +2) -8 . . . . . .  multiply by 4

  3x -4y = 2 . . . . . . . . . . add 2-4y

Answer:

1.406×[tex]10^{[tex]10^{18}km cubed

Step-by-step explanation:

The volume of a sphere is

[tex]V=\frac{4}{3}\pi r^3[/tex]

Filling in our formula:

[tex]V=\frac{4}{3}\pi (695,000)^3[/tex]

Cubing first gives us:

[tex]V=\frac{4}{3}\pi (3.35702[/tex]×[tex]10^{17}[/tex]

Do the multiplication and division of those numbers, multiply in the value of pi on your calculator, and you'll get 1.406×[tex]10^{18}[/tex]

To determine the volume of the Sun with a radius of about 695,000 km, we first convert the radius to centimeters and then apply the formula V = (4/3)πr³. After performing the calculations, the volume of the Sun is approximately 1.401 x 10³³ cm³in scientific notation with three decimal places in the mantissa.

The student has asked what the volume of the Sun is, given its radius of about 695,000 km. To find the volume of a sphere, the formula to use is V = (4/3)πr³, where V represents the volume and r is the radius.

First, we need to convert the radius from kilometers to centimeters because the standard unit for volume in scientific notation often involves cubic centimeters. There are 100,000 centimeters in a kilometer, so the radius in centimeters is 695,000 km × 100,000 cm/km = 6.95 x 10¹⁰cm.

Now, we can calculate the volume using the formula:

V = (4/3)π(6.95 x 10¹⁰ cm)³

V = (4/3)π(6.95^3 x 10³⁰) cm³

V = (4/3)π(334.14 x 10³⁰) cm³

V = (4/3)π(3.3414 x 10³²) cm³

V ≈ 4.1888 x 3.3414 x 10³² cm³

V ≈ 1.401 x 10^33 cm³

Therefore, the volume of the Sun in scientific notation, using three decimal places in the mantissa, is approximately 1.401 x 10³³ cm³.

https://brainly.com/question/12053350

#SPJ2

Answer:

The distance is  4.726

Step-by-step explanation:

we need to find the distance from the point to the line

Given:- point (-1,-2,1) and line ; x=4+4t, y=3+t, z=6-t .

used formula [tex]d=\frac{|a\times b|}{|a|}[/tex]

Let point P be (-1,-2,1)

using value t=0 and t=1

The point Q (4 , 3, 6) and R ( 8, 4, 5)

Let a be the vector from Q to R :   a = < 8 - 4, 4 - 3, 5 - 6 > = < 4, 1, -1 >

Let b be the vector from Q to P:    b = < -1 - 4, -2 - 3, 1 - 6> = < -5, -5, -5 >

The cross product of a and b is:

[tex]a \times b= \begin{vmatrix} i & j & k\\ 4 &1&-1\\-5 &-5&-5\\ \end{vmatrix}[/tex]

= -6i+15j-15k

The distance is : [tex]d=\frac{\sqrt{(-6)^{2}+(15)^{2}+(-15)^{2}}}{\sqrt{(4)^{2}+(1)^{2}+(-1)^{2}}}[/tex]

[tex]=\frac{\sqrt{36+225+225}}{\sqrt{16+1+1}}[/tex]

[tex]=\frac{\sqrt{36+225+225}}{\sqrt{16+1+1}}[/tex]

[tex]d=\frac{\sqrt{486}}{\sqrt{18}}[/tex]

≈4.726

Therefore, the distance is  4.726

Answer:

5.(3)

Step-by-step explanation:

5.(3)=16/3

Answer:

d

Step-by-step explanation:

Answer:

Quincy

Step-by-step explanation:

Each student is assigned a two digit number, so let's split the random number line into two digit numbers:

59, 78, 44, 43, 12, 15, 95, 40, 92, 33, 00, 04, 67, 43, 18, 02, 61, 05, 73, 96, 16, 84, 33, 84, 54

Now let's identify the numbers between 00 and 29.

59, 78, 44, 43, 12, 15, 95, 40, 92, 33, 00, 04, 67, 43, 18, 02, 61, 05, 73, 96, 16, 84, 33, 84, 54

So the fifth student in the list is #18, or Quincy.

Answer:

Quincy is the answer

Step-by-step explanation:

Answer:

[tex]\large\boxed{x=\dfrac{k-14}{5}}[/tex]

Step-by-step explanation:

[tex]5x=k-14\qquad\text{divide both sides by 5}\\\\\dfrac{\not5x}{\not5}=\dfrac{k-14}{5}\\\\x=\dfrac{k-14}{5}[/tex]

Answer:

[tex]5x = k - 14 \\ \frac{5x}{5} = \frac{k - 14}{5} \\ x = \frac{k - 14}{5} [/tex]

The residual for the newborn is -0.9148 kg, indicating he is lighter than what the model predicts for his length.

To calculate the residual for the newborn's weight, we first use the least squares regression line equation, which is weight = -5.33 + 0.1926 * length. We then input the newborn's length of 48 cm into the equation to predict the weight.

Predicted weight = -5.33 + (0.1926 * 48) = -5.33 + 9.2448 = 3.9148 kg

The residual is the difference between the actual weight and the predicted weight, so for this newborn, the residual = actual weight - predicted weight = 3 kg - 3.9148 kg = -0.9148 kg.

The negative residual indicates that the newborn weighs less than what the regression model predicts for a boy of 48 cm in length. This could suggest that the child is lighter than average for his length

ANSWER

36,-36

EXPLANATION

The given function is:

[tex]f(x) = {x}^{2} + 12x + 6[/tex]

To write this function in vertex form;

We need to add and subtract the square of half the coefficient of x.

The coefficient of x is 12.

Half of it is 6.

The square of 6 is 36.

Therefore we add and subtract 36.

Hence the zero pair is:

36, -36.

The correct answer is D.

Answer:

Last option: 36,-36​

Step-by-step explanation:

The vertex form of the function of a parabola is:

[tex]y=a(x-h)^2+k[/tex]

Where (h,k) is the vertex.

To write the given function in vertex form, we need to Complete the square.

Given the Standard form:

[tex]y=ax^2+bx+c[/tex]

We need to add and subtract [tex](\frac{b}{2})^2[/tex] on one side in order to complete the square.

Then, given [tex]y=x^2+12x+6[/tex], we know that:

[tex](\frac{12}{2})^2=6^2=36[/tex]

Then, completing the square, we get:

 [tex]y=x^2+12x+(36)+6-(36)[/tex]

[tex]y=(x+6)^2-30[/tex] (Vertex form)

Therefore, the answer is: 36,-36​

Answer: Probability that the entire batch will be rejected is 0.611.

Step-by-step explanation:

Since we have given that

Number of clock radios in a batch = 8000

Probability of defective clock radio = 7%

According to question, we have mentioned that A sample of 13 clock radios is randomly selected without replacement from the​ 8,000 and tested.

We will use "Binomial distribution":

here, n = 13 and

p (probability of success) = 7% = 0.07

so, we need to find that

P(the entire batch will be rejected)  = P(at least one of those test is defected)

So, it becomes,

P(at least one of those tested is defective) = 1 - P(none are defective)

So, P(none are defective ) is given by

[tex](1-0.07)^{13}\\\\=0.93^{13}\\\\=0.389[/tex]

So, P(at least one of those tested is defective) = 1 - P(none are defective)

                                                                             =  1 -  0.389

                                                                             =  0.611

Hence, Probability that the entire batch will be rejected is 0.611.

[tex]|\Omega|={_{53}C_3}\cdot 45=\dfrac{53!}{3!50!}\cdot45=\dfrac{51\cdot52\cdot53}{2\cdot3}\cdot45=1054170\\|A|=1\\\\P(A)=\dfrac{1}{1054170}\approx0.00000095\%[/tex]

Answer:

First brand of antifreeze: 21 gallons

Second brand of antifreeze: 9 gallons

Step-by-step explanation:

Let's call A the amount of  first brand of antifreeze. 20% pure antifreeze

Let's call B the amount of second brand of antifreeze. 70% pure antifreeze

The resulting mixture should have 35% pure antifreeze, and 30 gallons.

Then we know that the total amount of mixture will be:

[tex]A + B = 30[/tex]

Then the total amount of pure antifreeze in the mixture will be:

[tex]0.2A + 0.7B = 0.35 * 30[/tex]

[tex]0.2A + 0.7B = 10.5[/tex]

Then we have two equations and two unknowns so we solve the system of equations. Multiply the first equation by -0.7 and add it to the second equation:

[tex]-0.7A -0.7B = -0.7*30[/tex]

[tex]-0.7A -0.7B = -21[/tex]

[tex]-0.7A -0.7B = -21[/tex]

               +

[tex]0.2A + 0.7B = 10.5[/tex]

--------------------------------------

[tex]-0.5A = -10.5[/tex]

[tex]A = \frac{-10.5}{-0.5}[/tex]

[tex]A = 21\ gallons[/tex]

We substitute the value of A into one of the two equations and solve for B.

[tex]21 + B = 30[/tex]

[tex]B = 9\ gallons[/tex]

Answer:

[tex]\large\boxed{(f-g)(x)=-3x+11}[/tex]

Step-by-step explanation:

[tex](f-g)(x)=f(x)-g(x)\\\\f(x)=2x-1+3=2x+2\\g(x)=5x-9\\\\\text{Substitute:}\\\\(f-g)(x)=(2x+2)-(5x-9)\\\\=2x+2-5x-(-9)\\\\=2x+2-5x+9\qquad\text{combine like terms}\\\\=(2x-5x)+(2+9)\\\\=-3x+11[/tex]

Answer:

[tex]\bullet\ \ 0.\overline{15}[/tex]

Step-by-step explanation:

  5/33 = (5·3)/(33·3) = 15/99 = 0.151515151515...

_____

You may recall that 1/9 = 0.11111...(repeating indefinitely). That is, a multiple of 1/9 is a single-digit repeating decimal.

Likewise, 1/99 = 0.01010101...(repeating indefinitely). This means when a 2-digit numerator has 99 as the denominator, the decimal equivalent is that number repeated indefinitely. Any fraction with 999 as the denominator is a 3-digit repeat in decimal; 9999 as the denominator gives a 4-digit repeat, and so on.

Answer:

The correct option is 2.

Step-by-step explanation:

Let A be the event that the college student belongs to a health club and B be the event that the college student lives off-campus.

The probability that a college student belongs to a health club is 0.3.

[tex]P(A)=0.3[/tex]

The probability that a college student lives off-campus is 0.4.

[tex]P(B)=0.4[/tex]

The probability that a college student belongs to a health club and lives off-campus is 0.12.

[tex]P(A\cap B)=0.12[/tex]

The probability that a college student belongs to a health club OR lives off-campus is

[tex]P(A\cup B)=P(A)+P(B)-P(A\cap B)[/tex]

[tex]P(A\cup B)=0.3+0.4-0.12[/tex]

[tex]P(A\cup B)=0.58[/tex]

The probability that a college student belongs to a health club OR lives off-campus is 0.58. Therefore the correct option is 2.

Answer:

Step-by-step explanation:

Since we want twice as much Mocha as Decaf, we can create a "bag" that contains 2 lbs of Mocha (at 11.50 each) and 1 lb of Decaf (at 10). The value of this "bag" is then 2×11.50 +10.00 = 33.00. For 181.50, we can buy ...

  181.50/33.00 = 5.5

"bags". This amount is ...

  11 lbs of Arabian Mocha and 5.5 lbs of Columbian Decaf

Answer:

A. -1.6; not significant

Step-by-step explanation:

The z-score of a data set that is normally distributed with a mean of [tex]\bar x[/tex] and a standard deviation of [tex]\sigma[/tex], is given by:

[tex]z=\frac{x-\bar x}{\sigma}[/tex].

From the question, the test score is: [tex]x=48.4[/tex], the mean is [tex]\bar x=66[/tex], and the standard deviation is [tex]\sigma =11[/tex].

We just have to plug these values into the above formula to obtain:

[tex]z=\frac{48.4-66}{11}[/tex].

This simplifies to:  [tex]z=\frac{-17.6}{11}[/tex].

[tex]z=-1.6[/tex].

We can see that the z-score falls within two standard deviations of the mean.

Since [tex]-2\le-1.6\le2[/tex] the value is not significant.

The correct answer is A. -1.6; not significant

By Stokes' theorem,

[tex]\displaystyle\int_C\vec F\cdot\mathrm d\vec r=\iint_S(\nabla\times\vec F)\cdot\mathrm d\vec S[/tex]

where [tex]S[/tex] is the surface with [tex]C[/tex] as its boundary. The curl is

[tex]\nabla\times\vec F(x,y,z)=2\,\vec\imath-x\,\vec k[/tex]

Parameterize [tex]S[/tex] by

[tex]\vec\sigma(u,v)=u\cos v\,\vec\imath+u\sin v\,\vec\jmath+(8-u\cos v)\,\vec k[/tex]

with [tex]0\le u\le9[/tex] and [tex]0\le v\le2\pi[/tex]. Then take the normal vector to [tex]S[/tex] to be

[tex]\vec\sigma_u\times\vec\sigma_v=u\,\vec\imath+u\,\vec k[/tex]

Then the line integral is equal to the surface integral,

[tex]\displaystyle\iint_S(\nabla\times\vec F)\cdot\mathrm d\vec S=\int_0^{2\pi}\int_0^9(2\,\vec\imath-u\cos v\,\vec k)\cdot(u\,\vec\imath+u\,\vec k)\,\mathrm du\,\mathrm dv[/tex]

[tex]\displaystyle=\int_0^{2\pi}\int_0^9(2u-u^2\cos v)\,\mathrm du\,\mathrm dv=\boxed{162\pi}[/tex]