: For the following concrete beam cross$-$section with concrete strength $f_c=4000$ psi and

ASTM A$615$ Grade $60$ reinforcement, find the following:

a$)$ The Moment of Inertia of the composite cross

section and associated neutral axis

b$)$ The nominal moment capacity $(M_n)$ of the section

per ACI $318$

c$)$ The factored moment capacity $(M_n)$ of the section

per ACI $318$