[单选题]
A 60-kg skier starts from rest from the top of a(xz s 82g9fmosel )q;z 50-m high slope. If th1ni1 8faltgwa9)f. tve work done81tiavt l1 w n9ffa.g) by friction is $-6.0 \times 10^{3} \; J$, what is the speed of the skier on reaching the bottom of the slope?
