Work is required to lift a body through a height from the ground. Prove the law of conservation of energy of a freely falling body

State and prove the law of conservation of energy for a freely falling body.

Prove conservation of energy for a freely falling body.

Work is required to lift a body through a height from the ground, Draw the variation of KE and PE with the height of the body.

Work is required to lift a body through a height from the ground, Calculate the work done in lifting a body of mass 10 kg to a height of 10m above the ground.

Show that total mechanical energy is conserved for a freely falling body.

Force is required to lift a body from the ground to a height h and work is measured as the product of force and magnitude of displacement. A man of mass 60 kg carries a stone of mass 20 kg to the top of a multistoreyed building of height 50 m . Calculate the total energy spent by him? (g= 9.8 m/s^2)

More force is required to push a body than pull to get same speed on a ground with same friction. Why?