Help me please I couldn’t get the answer, was kinda hard ,,please help!

Find the volume of the solid generated when the region bounded by y= x and y= 4√x is revolved about the x-axis the volume of the solid is: (type an exact answer cubic units)

Arestaurant offers a $12 dinner special that has 5 choices for an appetizer, 12 choices for an entrée, and 4 choices for a dessert. how many different meals are available when you select an appetizer, an entrée, and a dessert? a meal can be chosen in nothing ways. (type a whole number.)

If a runner who runs at a constant speed of p miles per hour runs a mile in exactly p minutes what is the integer closest to the value p