A heavy book lies still on a table. Rohit says only gravity acts on it, and the table merely…

Why

Rohit's objection is a fair one — a table is not alive, so saying it 'pushes' sounds odd, and that discomfort is honest thinking. But follow his idea through: if gravity were the only force, nothing would balance it and the book would be accelerating downward right now. It is not moving at all, so something must be pushing up exactly as hard. A tabletop is a very stiff spring; the book squashes it by an amount too small for your eye, and it presses back. Test: lay the same book on a thin plastic scale bridged across two bricks — now you SEE the bend, and you can feel it press up. Priya is right: when something sits still, the forces on it are balanced, not absent.