4in x 18in^2= 72 inches cubed
63 m3
9×2=18
18×7=126
126÷2=63
Answer: 
Step-by-step explanation:
Here the give expression is,

We can write,
( because
)

⇒ Option D is correct.
Answer:
28
Step-by-step explanation:
Since B is the midpoint of AC, that means AB = BC. That means 3x+4 = 5x-6. We can now set up an equation to solve for x:
3x+4 = 5x-6
3x+10 = 5x
10 = 2x
x = 5
Now that we know what x is, we can just plug x into the expression of AB and multiply it by 2:
(3*(5)+4)*2
=(15+4)*2
=19*2
=28
(side note: we could have plugged x into the expression of BC as well, but in this case plugging it into AB tends to be easier to solve)
Therefore, the length of AC is 28.
Answer:
The circulation of the field f(x) over curve C is Zero
Step-by-step explanation:
The function
and curve C is ellipse of equation

Theory: Stokes Theorem is given by:

Where, Curl f(x) = ![\left[\begin{array}{ccc}\hat{i}&\hat{j}&\hat{k}\\\frac{∂}{∂x} &\frac{∂}{∂y} &\frac{∂}{∂z} \\F1&F2&F3\end{array}\right]](https://tex.z-dn.net/?f=%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D%5Chat%7Bi%7D%26%5Chat%7Bj%7D%26%5Chat%7Bk%7D%5C%5C%5Cfrac%7B%E2%88%82%7D%7B%E2%88%82x%7D%20%26%5Cfrac%7B%E2%88%82%7D%7B%E2%88%82y%7D%20%26%5Cfrac%7B%E2%88%82%7D%7B%E2%88%82z%7D%20%5C%5CF1%26F2%26F3%5Cend%7Barray%7D%5Cright%5D)
Also, f(x) = (F1,F2,F3)

Using Stokes Theorem,
Surface is given by g(x) = 
Therefore, tex]\hat{N} = grad(g(x))[/tex]


Now, 
Curl f(x) = ![\left[\begin{array}{ccc}\hat{i}&\hat{j}&\hat{k}\\\frac{∂}{∂x} &\frac{∂}{∂y} &\frac{∂}{∂z} \\F1&F2&F3\end{array}\right]](https://tex.z-dn.net/?f=%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D%5Chat%7Bi%7D%26%5Chat%7Bj%7D%26%5Chat%7Bk%7D%5C%5C%5Cfrac%7B%E2%88%82%7D%7B%E2%88%82x%7D%20%26%5Cfrac%7B%E2%88%82%7D%7B%E2%88%82y%7D%20%26%5Cfrac%7B%E2%88%82%7D%7B%E2%88%82z%7D%20%5C%5CF1%26F2%26F3%5Cend%7Barray%7D%5Cright%5D)
Curl f(x) = ![\left[\begin{array}{ccc}\hat{i}&\hat{j}&\hat{k}\\\frac{∂}{∂x} &\frac{∂}{∂y} &\frac{∂}{∂z} \\x^{2}&4x&z^{2}\end{array}\right]](https://tex.z-dn.net/?f=%5Cleft%5B%5Cbegin%7Barray%7D%7Bccc%7D%5Chat%7Bi%7D%26%5Chat%7Bj%7D%26%5Chat%7Bk%7D%5C%5C%5Cfrac%7B%E2%88%82%7D%7B%E2%88%82x%7D%20%26%5Cfrac%7B%E2%88%82%7D%7B%E2%88%82y%7D%20%26%5Cfrac%7B%E2%88%82%7D%7B%E2%88%82z%7D%20%5C%5Cx%5E%7B2%7D%264x%26z%5E%7B2%7D%5Cend%7Barray%7D%5Cright%5D)
Curl f(x) = (0,0,4)
Putting all values in Stokes Theorem,



I=0
Thus, The circulation of the field f(x) over curve C is Zero