A piece of iron at a temperature of 145°C cools off to a temperature of 45.0°C. If the iron has a maşs of 10.0 g and a specific heat of 0.449 J/g.°C, how much heat is given up?

Where is the potential energy throughout the loading, cocking, and releasing of the trebuchet?

The electric field between square plates of a parallel-plate capacitor has magnitude e. the potential across the plates is maintained with constant voltage by a battery as they are pulled apart to twice their original separation, which is small compared to the dimensions of the plates. the magnitude of the electric field between the plates is now equal to a)e b)e/4 c)e/2 d)4e e)2e

It is really hard for me right know