Aball is thrown with a velocity of 20.0m/s 30° and travels 3.30 s before it hits the ground what is the height from which it was thrown

Inner peace.. jk it's  a stable electron configuration

Answer(a)   the matererials that are in contact, the two materials and the nature of their surfaces/// (b)/// the force pushing the two surfaces together, pushing the surfaces together causes the more of the asperities to come together and increases the surface area in contact with each other

Ithink it's  c. i'm sure