AAA Company's standard labor cost per unit of output is $$50(4$ hours x $$12\mathrm{.}50$ per hour$).$ During April, the company incurs $400$ hours of direct labor at a total cost of $$6,000$ in making $110$ units of finished product.

a$.$ Show the SH$,$ SR$,$ AH$,$ and AR$.$

b$.$ Compute the total labor variance, labor price variance, and labor quantity variance.