According to the SGI Air Brake Manual, how far below the cut-out pressure does the governor normally let reservoir pressure fall before it cuts the compressor back in?

1. About 5 to 10 psi (34 to 69 kPa)
2. About 20 to 25 psi (138 to 172 kPa)
3. About 40 to 50 psi (276 to 345 kPa)
4. About 60 to 70 psi (414 to 483 kPa)