$R_C = 200(8) - 900 = 700 \, \text{ lb}$
$M_C = 200(8)(4) - 900(6) = 1000 \, \text{ lb}\cdot\text{ft}$
$t_{B/C} = \dfrac{1}{EI}(Area_{BC}) \, \bar{X}_B$
$t_{B/C} = \dfrac{1}{(1.5 \times 10^6)(60)} [ \, \frac{1}{2}(6)(4200)(2) - 1000(6)(3) - \frac{1}{3}(6)(3600)(15) \, ] (12^3)$
$t_{B/C} = -0.06912 \, \text{ in}$
∴ δ = 0.06912 inch downward answer