By using Unit Load Method, find the

$($a$)$ the horizontal displacement at roller D $(H,C)$

$($b$)$ the rotation at support hinge $A({}_A)$ of the rigid frame shown below. Use $E=200k\frac{N}{m}{m}^2$;$I={10}^{9}m{m}^4.$

Can show me how to do this question unit load method