Finding spring constant given displacement of spring and distance traveled by a cart

Gunpowder residue is most likely to show up where on a shooters hands

Which is an example of gaining a static charge by conduction? a) rubbing a balloon against your hair. b) shuffling your shoes across a carpet. c) bringing a charged rod near an electroscope. d) touching your car on a cold day and getting a shock.

Aman throws a football straight into the air. as it rises, it slows down. which type of energy is the football gaining?