Energy, work and power — practice question

A smooth slide $AB$ is positioned so that its top end $A$ lies $3\,\text{m}$ above level ground. Point $B$ is $h\,\text{m}$ above the ground. A particle $P$ of mass $0.2\,\text{kg}$ is let go from rest at a point on the slide. It travels down the slide and, after going past $B$, keeps moving until it reaches the ground. The speed of $P$ at $B$ is $v_B$ and the speed at which $P$ hits the ground is $v_G$.