Its B just took the test the answer is B
Assuming the area below the line y=0 (i.e. x>1) does NOT count, the area to be rotated is shown in the graph attached.
A. Again, using Pappus's theorem,
Area, A = (2/3)*1*(1-(-1))=4/3 (2/3 of the enclosing rectangle, or you can integrate)
Distance of centroid from axis of rotation, R = (2-0) = 2
Volume = 2 π RA = 2 π 2 * 4/3 = 16 π / 3 (approximately = 16.76 units)
B. By integration, using the washer method
Volume =


![=2\pi[x^4/4-2x^3/3-x^2/2+2x]_{-1}^{1}](https://tex.z-dn.net/?f=%3D2%5Cpi%5Bx%5E4%2F4-2x%5E3%2F3-x%5E2%2F2%2B2x%5D_%7B-1%7D%5E%7B1%7D)
![=2\pi([1/4-2/3-1/2+2]-[1/4+2/3-1/2-2])](https://tex.z-dn.net/?f=%3D2%5Cpi%28%5B1%2F4-2%2F3-1%2F2%2B2%5D-%5B1%2F4%2B2%2F3-1%2F2-2%5D%29)

= 16 π /3 as before
A+b=(-3n+2)+(5n-7)
=(5-3n)+(2-7)
=2n-5
Came up with the same answer as the first guy
Answer:

Step-by-step explanation:
The formula for the accrued amount from compound interest is

1. Amount in account on 1 Jan 2015
(a) Data:
a = £23 517.60
r = 2.5 %
n = 1
t = 1 yr
(b) Calculations:
r = 0.025

The amount that gathered interest was £22 944.00 but, before the interest started accruing, Carol had withdrawn £1000 from the account.
She must have had £23 944 in her account on 1 Jan 2015.
(2) Amount originally invested
(a) Data
A = £23 944.00

3. Summary
1 Jan 2014 P = £23 360.00
1 Jan 2015 A = 23 944.00
Withdrawal = <u> -1 000.00
</u>
P = 22 944.00
1 Jan 2016 A = £23 517.60