Please be honest :( I’ll mark u please help

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.

Math i have no idea how to do a and b

Nicole purchased a container of cashews that weighs 5 kilograms. zion purchased a container of cashews that weighs 4,900 grams. how many more grams of cashews did nicole purchase?