What is gravity? im dumb

When a spring is compressed, the energy changes from kinetic to potential. which best describes what is causing this change? work power gravitational energy chemical energy

Give an example for each of the following situations: 1) negative acceleration, but positive velocity 2) positive acceleration and positive velocity 3) positive acceleration, but negative velocity 4) negative acceleration and negative velocity 5) positive velocity and no acceleration

1,990,000,000,000,000,000,000,000,000,000 in scientific notation