Please help! I really need it.

What is the mass of the water that is being heated? it requires 2,500 joules to raise a certain amount of water (c = 4.186 jig c) from 20.0°c to 60.0°c. o 159 o 40 g o 63 g o 80 g

Ahot-air balloon is 11.0 m above the ground and rising at a speed of 7.00 m/s. a ball is thrown horizontally from the balloon basket at a speed of 9.00 m/s. ignore friction and air resistance and find the speed of the ball when it strikes the ground.

Assume that two of the electrons at the negative terminal have attached themselves to a nearby neutral atom. there is now a negative ion with a charge -2e at this terminal. what are the electric potential and electric potential energy of the negative ion relative to the electron? the electric potential and the electric potential energy are both twice as much. the electric potential is twice as much and the electric potential energy is the same. the electric potential is the same and the electric potential energy is twice as much. the electric potential and the electric potential energy are both the same. the electric potential is the same and the electric potential energy is increased by the mass ratio of the oxygen ion to the electron. the electric potential is twice as much and the electric potential energy is increased by the mass ratio of the oxygen ion to the electron.