A solid circular titanium control rod at 7,000 lb axial tension force where stress must not exceed 42,000 psi. Assume that the modulus of elasticity of the titanium is 16,500,000 psi and that the rod must elongate no more than 0.20 in. Determine (a) the minimum rod diameter (precision 0.00) and (b) the maximum rod length (precision of 1).