Abook on 2- meter high shelf has 20 joules of potential energy? what is the mass of this book?me.

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

What is the coefficient of kinetic friction μk between the block and the tabletop?

It is reasonable to assume that the bulk modulus of blood is about the same as that of water (2.2 gpa). as one goes deeper and deeper in the ocean, the pressure increases by 10000 pa for every meter below the surface. if a diver goes down 80.0 m in the ocean, by how much does each cubic centimeter of her blood change in volume? give the answer in cubic centimeters (actually one cubic centimeter equals one milliliter).