Express 66 as a product of its prime factors

Acar started driving from city a to city b, distance between which is 620 miles, at a rate of 60 mph. two hours later a truck left city b and started moving towards city a at a rate of 40 mph. what distance from city a is the point where the truck and the car will meet?

Use the given information to determine the exact trigonometric value.

Find the volume of the solid bounded by the plane z=0 and the paraboloid z=1-x^2 –y^2