고체역학 (Beer) — Pure Bending: Problem 4.51

4.51 Knowing that the bending moment in the reinforced concrete beam is $+100 \text{ kip}\cdot\text{ft}$ and that the modulus of elasticity is $3.625 \times 10^6 \text{ psi}$ for the concrete and $29 \times 10^6 \text{ psi}$ for the steel, determine (a) the stress in the steel, (b) the maximum stress in the concrete.