When an object of mass 50 kg is moved from one point to another along a straight horizontal line, what is the work done by the gravitational force on the object? (Take g = 10 m/s2)

How is work defined in physics?

It is easier to roll a stone uphill on a sloped road than to lift it vertically upward because:

The gravitational potential energy of an object at a height is the work done to lift it from the ground to that height _____________.