Suppose that the pitch of the threads of the turnbuckle is p = 0.05 in, their mean radius...

Suppose that the pitch of the threads of the turnbuckle is p = 0.05 in, their mean radius is r = 0.25 in, and the coefficient of static friction between the threads and the mating grooves is 0.24. If T = 200 lb, what couple must be exerted on the turnbuckle to start loosening it?