15. A kitten is sitting stationary on a skateboard. The kitten has a mass of 1.25 kg, and the skateboard has a mass of 3.5 kg. If the kitten remained on the skateboard while being pushed, what force would be
required to achieve an acceleration of 2.0 m/s2? Ignore friction.

Aplayground slide is 8.80 ft long and makes an angle of 25.0° with the horizontal. a 63.0-kg child, initially at the top, slides all the way down to the bottom of the slide. (a) choosing the bottom of the slide as the reference configuration, what is the system's potential energy when the child is at the top and at the bottom of the slide? what is the change in potential energy as the child slides from the top to the bottom of the slide? (include the sign of the value in your answer.)