AP Physics C Unit 3 Work and Kinetic Energy

A 50 kg skater is gliding along the ice, heading due north at 4.0 m/s. The ice has a small coefficient of static friction, to prevent the skater from slipping sideways, but kinetic friction is zero. Suddenly, a wind from the northeast exerts a force of 4.0 N on skater. a. Use work and energy to find the skater's speed after gliding 100 m in this wind. b. What is the minimum value of coefficient of static friction that allows her to continue moving straight north?