Plywood roof sheathing for a house is placed on roof trusses 24 inches on centers. The edges of the plywood are un-blocked. The panels are attached with the face grain of the plywood turned perpindicular to the trusses. According to the Code, the minimum thickness of the plywood should be ____?

Plywood roof sheathing for a house is placed on roof trusses 24 inches on centers. The edges of the plywood are un-blocked. The panels are attached with the face grain of the plywood turned perpindicular to the trusses. According to the Code, the minimum thickness of the plywood should be ____?