Three people pull simultaneously on a stubborn donkey. Jack pulls directly ahead of the donkey with a force of 81.7 N, Jill pulls with 91.9 N in a direction 45° to the left, and Jane pulls in a direction 45° to the right with 151 N. (Since the donkey is involved with such uncoordinated people, who can blame it for being stubborn?) Find the magnitude of the net force the people exert on the donkey.