If a pull of 350 N accelerates a 38-kg child on ice skates at a rate of 7.3 \frac{m}{s^2}, what is the frictional force acting on the skate?

Fap-Fk = m*a

350-Fk = 38*7.3 = 277.4
-Fk = 277.4-350 = -72.6
Fk = 72.6 N. = Force of kinetic friction.