Use all three of Newton's laws of motion to describe what happens when a car starts
off at rest, is pushed across a platform, and
then accelerates downward.

Initially the car is at rest (.Newton’s 1st Law says the car will remain at rest unless an unbalanced force acts). When pushed, the contact force on the car is equal to an equal force on the person pushing it (Newton’s 3rd Law). If the forces on the car are unbalanced it will accelerate downward (Newton’s 2nd law= the force is equal to the rate of change of momentum of the car)

Neptune is the eighth planet from the sun. it was the first planet to get its existence predicted by  mathematical calculations  before it was actually seen through a telescope on sept. 23, 1846. irregularities in the orbit of  uranus  led french astronomer alexis bouvard to suggest that the gravitational pull from another celestial body might be responsible. german astronomer johann galle then relied on subsequent calculations to   spot neptune via telescope. previously, astronomer galileo galilei sketched the planet, but he mistook it for a star due to its slow motion. in accordance with all the other planets seen in the sky, this new world was given a name from greek and roman mythology — neptune, the roman god of the sea.

Velocity is the speed of an object in a certain direction so you'd need to know speed and direction