I’m doing this too hopefully someone answers quick cause I’m confused also.
Replace x with π/2 - x to get the equivalent integral

but the integrand is even, so this is really just

Substitute x = 1/2 arccot(u/2), which transforms the integral to

There are lots of ways to compute this. What I did was to consider the complex contour integral

where γ is a semicircle in the complex plane with its diameter joining (-R, 0) and (R, 0) on the real axis. A bound for the integral over the arc of the circle is estimated to be

which vanishes as R goes to ∞. Then by the residue theorem, we have in the limit

and it follows that

I know it's late but,
25 ft ÷ 4 cm = 6.25
500 ÷ 6.25 = 80
750 ÷ 6.25 = 120
and so your answer is C.<span> 80 centimeters by 120 centimeters
and again sorry it's late :D</span>
So you can set up proportion.

Here, you need to solve for C.
You can do that by multiple both sides by 360 and then you should get

Hope this helps.
The perimeter of these can be found by adding length and width and then multiplying by two.
Rectangle A: (with all of the variables already doubled)
2x + 16 + 2x - 2
2x + 2x + 16 - 2
4x + 14
So rectangle A's perimeter is 4x + 14.
Rectangle B: (Still with all the variables already doubled)
8x + 10 + 6x - 4
8x + 6x + 10 - 4
14x + 6
So rectangle B's perimeter is 14x + 6
And now to subtract the two.
(7x + 3) - (4x + 14)
14x + 6 - 4x - 14
14x - 4x + 6 - 14
10x - 8
So it would be C.