What is the volume of the solid generated when the region bounded by the graph of y = 4x, the horizontal line y = 8, and the y-axis is revolved about the horizontal line y = 8 ? (CALCULUS HELP WILL VOTE BRAINLIEST)

Can someone me with #s 8, 9, and 11. with just one of the three also works. prove using only trig identities.

If f(x) = 4 - x2 and g(x) = 6x, which expression is equivalent to (g-f)(3)? 06-3-(4 + 3)2 06-3-(4-33 6(3) - 4 +32 6(3) -4 -32

Money off coupons have been circulated to 300 households. only 2/5 of these were redeemed (used) in the local supermarket to get a free shampoo. what fraction of coupons were unused? (ps: write how you got the answer)