1. A 20°-pressure-angle, 30°-helix-angle, 27-tooth helical gear has a diametral pitch pd = 5. Find the pitch diameter, addendum, dedendum, outside diameter, normal, transverse, and axial pitch.
2. A 25°-pressure-angle, 20°-helix-angle, 43-tooth helical gear has a diametral pitch pd = 8. Find the pitch diameter, addendum, dedendum, outside diameter, normal, transverse, and axial pitch.
3. A 57-tooth, 10°-helix-angle, helical gear is in mesh with a 23-tooth pinion. The pd = 6 and φ = 25°. Find the transverse and axial contact ratios.
4. A 78-tooth, 30°-helix-angle, helical gear is in mesh with a 27-tooth pinion. The pd = 6 and φ = 20°. Find the transverse and axial contact ratios.