Answer:
Variable overhead efficiency variance $1,680 Â Favorable
Explanation:
Variable overhead efficiency variance: Â Variable overhead efficiency variance aims to determine whether or not their exist savings or extra cost incurred on variable overhead as a result of workers being faster or slower that expected.
Since the variable overhead is charged using labour hours, any amount by which the actual labour hours differ from the standard allowable hours would result in a variance
                                                   Hours
5000 units should have taken (5000×0.5 hours)           2,500
but did take                                         2,080 Â
Labour hours variance                                 420  favorable
Standard variable overhead rate                       ×$ 4.00 per hour
Variable overhead efficiency variance                  $1,680  Favorable
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