When riding a 10-speed bicycle up a hill, a cyclist shifts the chain to a larger-diameter gear attached to the back wheel. What must be true when the cyclist shifts to a larger gear?
a. The torque exerted by the chain on the gear is larger.
b. The force exerted by the chain on the gear is larger.
c. The cyclist pedals more frequently to travel the same distance.
d. Both a and c are correct.
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