A person is on crutches. The person weighs 170 lbs. As seen from the front, each light crutch makes an angle of 22° with the vertical. Half of the person's weightis supported by the crutches. The other half is supported by the vertical forces of the ground on his feet. Assuming the person is moving with constant velocity and the force exerted by the ground on the crutches acts along the crutches, determine:
a) the smalles possible coefficient of friction between the crutches and the ground
b) the magnitude of the compression force in each crutch