It takes 444 newton to acceleration an object 7.0 m/s^2. What force was applied to the object?

When a 5.0kg cart undergoes a 2.2m/s increase in speed, what is the impulse of the cart

Astone weighing 1.5 kilograms is resting on a rock at a height of 20 meters above the ground. the stone rolls down 10 meters and comes to rest on a patch of moss. the gravitational potential energy of the stone on the moss is joules.

How do we measure or think of speed in the united states?