Determine the cаsting-pоsitiоn mоdificаtion fаctor, ψt, for a rectangular beam with b = 17 in. and d = 23 in., four galvanized No. 7 Grade 60 tension-reinforcement bars placed in the bottom of the beam, and No. 4 Grade 60 stirrups located every 8 in. along the span. Assume 8,000-psi normal-weight concrete and a clear cover of 1.75 in.