Direct Labor Variances

Alvarado Company produces a product that requires $9$ standard direct labor hours per unit at a standard hourly rate of $$12\mathrm{.}00$ per hour. If $3,500$ units used $30,900$ hours at an hourly rate of $$12\mathrm{.}36$ per hour, what is the direct labor $($a$)$ rate variance, $($b$)$ time variance, and $($c$)$ cost variance? Enter a favorable variance as a negative number using a minus sign and an unfavorable variance as a positive number.

a$.$ Direct labor rate variance

b$.$ Direct labor time variance

c$.$ Direct labor cost variance

$$