6. If y varies directly as x3, and y=54 when x=3, how will you find y when x=4?
7. If y varies directly as the square of x, and y=40 when x=4, how will you find y when x = -6?
8. A bomber-pilot coming out of a dive at a velocity of 600 feet per second experiences a centrifugal force of 1800 pounds. If centrifugal force is directly proportional to the square of velocity, find the force on this pilot flying the same path at 1000 feet per second.
