a) A car weighs 1500kg, if it is travelling at 7m/s, how much kinetic energy does it have?

To determine the kinetic energy of the car, we need to use the formula for kinetic energy. The formula is KE=(1/2)mv^(2) where m is the mass of the object (in kg) and v is the speed of the object (in meters per second, which is often written as (m/s)).
In the case we are looking at, our object is the car, the mass, m = 1500kg and the speed, v = 7m/s. Plugging these values into the formula for kinetic energy and using our calculator we get the following:
KE = (1/2)mv^(2) = (1/2)1500(7^(2)) = 36750J