When inspecting the rear shut-off valves (service and emergency) on a set of doubles before driving, what should the valve positions be?

49 CFR 383.115(e); AAMVA CDL Manual Section 7.3.1, p. 7-3

Shut-off valve position is what makes the "check air flows to all trailers" test in Section 7.4.1 work at all. Get it backwards and the rig will either fail to build air pressure or have no air reaching the rear brakes, making this one of the most frequently tested doubles/triples specifics on the real exam.