Whats his mistake and the correct awnser

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)

Write an equation in slope intercept form of the line passes through the given point and is parallel to the graph of the given equation (0,0); y=3/8 x+2

The height of a flare fired from the deck of a ship in distress can be modeled by h(t)= -2(8t^2-52t-28), where h is the height of the flare above water and t is the time in seconds. a. find the time it takes the flare to hit the water.