a candle of diameter d is floating on a liquid in a cylindrical container of D. if it burns at the rate of 2cm/hr, the top of the candle will ( ignore he volume change due to molten wax falling into the container)
1) remain at the same height
2) fall at the rate of 1cm/ hour
3) fall at the rate of 2cm /hour
4) go up at the rate of 1cm / hr