Select the correct product.

(x^2 + 4x + 8)(2x - 1)

a. 2x^3 + 7x^2 + 12x - 8
b. 2x^3 - 7x^2 - 12x - 8
c. x^2 + 6x + 7
d. x^2 + 8x - 8

Determine whether the following statements are true and give an explanation or counterexample. bold a. when using the shell method, the axis of the cylindrical shells is parallel to the axis of revolution. bold b. if a region is revolved about the y-axis, then the shell method must be used. bold c. if a region is revolved about the x-axis, then in principle it is possible to use the disk/washer method and integrate with respect to x or the shell method and integrate with respect to y.

Problem 3 a bank charges a service fee of $7.50 per month for a checking account. a bank account has $85.00. if no money is deposited or withdrawn except the service charge, how many months until the account balance is negative

A. 530 ft^2 b. 500 ft^2 c. 470 ft^2 d. 450 ft^2