The idler gear _____________. Group of answer choices is used primarily to change the direction of a gear train's output is the gear tied to the gear train's output is a gear set with multiple gears on one shaft is the gear that supplies power to the gear train, often tied to a motorThe drive gear _____________. Group of answer choices is used primarily to change the direction of a gear train's output is the gear that supplies power to the gear train, often tied to a motor is the gear tied to the gear train's output is a gear set with multiple gears on one shaft