1. Design a compound, reverted, spur gear train for a ratio of 75:1 and diametral pitch of 12. Specify pitch diameters and numbers of teeth. Sketch the train to scale.
2. Design a compound, reverted, spur gear train for a ratio of 7: 1 and diametral pitch of 4. Specify pitch diameters and numbers of teeth. Sketch the train to scale.