Please help me
Which one do I choose for each one

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.

Tan198=asin164=? how to solve this? ?

The measures of the angles in △abc are given by the expressions in the table. angle measure angle a 65° angle b (3x−10)° angle c (2x)∘ find the value of x. then find the m∠b and m∠c.