A cube of pine measures 2.5cm on each side. It's mass is 8.1g. That means its density is
g/cm3

An engineer designs a roller coaster so that a car travels horizontally for 162 ft, then climbs 127 ft at an angle of 31.0° above the horizontal. it then moves 127 ft at an angle of 46.0° below the horizontal. if we take the initial horizontal motion of the car to be along the +x-axis, what is the car's displacement? (give the magnitude of your answer, in ft, to at least four significant figures and give the direction of your answer in degrees counterclockwise from the +x-axis.)

What object a collides with object b and bounces back its final momentum is?

An automobile steering wheel is shown. what is the ideal mechanical advantage? if the ama is 8, what is the efficiency of the steering wheel?