The (partial) cost sheet for the single product manufactured at Briarcliff Corporation follows: The master budget level of production is 45,270 direct labor-hours, which is also the production volume used to compute the fixed overhead application rate. Other information available for operations over the past accounting period include the following: Required: a. What was the variable overhead efficiency variance? b. What was the fixed overhead price variance? c. What was the fixed overhead production volume variance? Note: For all requirements, Indicate the effect of each variance by selecting "F" for favorable, or "U" for unfavorable. If there is no effect, do not select either option