(Solved): An 824 in. (nominal) concrete masonry beam is reinforced with one No. 6 Grade 60 reinforcing bar ...

An $8\times 24$ in. (nominal) concrete masonry beam is reinforced with one No. 6 Grade 60 reinforcing bar positioned at $20\mathrm{in}$. from the compression face, as shown below. Calculate (a) the moment capacity $?M_n$ of the beam; and (b) check if the steel reinforcement has yielded or not using ${?}_s??{?}_y$; and (c) check if the steel reinforcement has yielded or not using the ratio of $c/d$. Assume $f_m^{?}=1500\mathrm{psi}$ and the tension reinforcement strain factor $?=1.5$.