Can I get some help with this please?

Draw the line of reflection that reflects △abc onto triangle δ a'b'c'

Olivia uses the work below to determine 55% of 720 which explains the error in olivia’s solution

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.