Repeat problem 1310 for a helical gearset with n = 20 and = 30. Problem 1310, for a spur gearset with = 20,

Repeat problem 13–10 for a helical gearset with φn = 20◦ and ψ = 30◦.
Problem 13–10, for a spur gearset with φ = 20◦, while avoiding interference, find:
(a) The smallest pinion tooth count that will run with itself
(b) The smallest pinion tooth count at a ratio mG = 2.5, and the largest gear tooth count possible with this pinion
(c) The smallest pinion that will run with a rack