$(6$pts$)$ Standard and actual costs for direct materials for the manufacture of $1,000$ units of product were as follows:

Actual costs Standard costs

Determine the:

$($a$)$ Price variance $$

$(AQ-SQ)SP$

$($b$)$ Quantity variance

$(9\mathrm{.}10-9\mathrm{.}00)-50$

$(1\mathrm{.}550-1,600)$

$-50$