A girl of mass m_G is walking up a slippery slope while pulling a sled of unknown mass; the slope makes an angle "theta" with the horizontal. The coefficient of static friction between the girl's boots and the slope is mu_s; the friction between the sled and the slope is negligible. It turns...
I have already done the force diagram and free body diagrams and such, as well as identified the action reaction pairs. I think their is an error in your calculation of m_s though, wouldn't it have to include "a" somewhere in there?