A=a-b/5+c solve for a

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.

Aculture started with 3000 bacteria. after 5 hours it grew to 3900 bacteria. predict how many bacteria will be present after 9 hours

In a column proof the right column states your reasons