What has to happen for a feather and a ball to fall at the same rate?

How does the amount of energy required to hold each proton and neutron in the nucleus compare to the energy released when they are removed?

Blank liquids and gases exert a buoyant force on objects placed in them

The amount of heat required to change liquid water to vapor at its boiling temperature is 2256 kj/kg. the amount of heat required to change liquid mercury to its vapor state at its boiling temperature is 295 kj/kg. one kg of each substance is currently at its boiling point. how will the amount of thermal energy required to change each substance from a liquid to a gas differ?