Bondi Corporation makes automotive engines. For the most recent month, budgeted production was $3,400$ engines. The standard

power cost is $$2\mathrm{.}20$ per machine$-$hour. The company's standards indicate that each engine requires $11\mathrm{.}2$ machine$-$hours. Actual

production was $3,700$ engines. Actual machine$-$hours were $39,740$ machine$-$hours. Actual power cost totaled $$89,780.$

Required:

Determine the rate and efficiency variances for the variable overhead item power cost. $($Indicate the effect of each variance by

selecting $"$F$"$ for favorable, $"$U$"$ for unfavorable, and "None" for no effect $($i$.$e$.,$ zero variance$).$ Input all amounts as positive values.$)$