Given: A standard 4″ by 1-1/2″ square J box has a conduit, connectors, but no other fittings or devices and is closed with a flat cover. There are no grounding conductors. What is the maximum number of size 12 AWG conductors permitted in this box?

Given: A standard 4″ by 1-1/2″ square J box has a conduit, connectors, but no other fittings or devices and is closed with a flat cover. There are no grounding conductors. What is the maximum number of size 12 AWG conductors permitted in this box?