Use the following information of Alfred Industries. Standard manufacturing overhead based on normal monthly volume: Fixed ($300,500 + 20,000 units) Variable ($100,000 + 20,000 units) Units actually produced in current month Actual overhead costs incurred (including $300,000 fixed) $15.03 5.00 $ 20.02 18,000 units $383,800 Compute the overhead spending variance and the volume variance. (Indicate the effect of each variance by selecting Favorable or Unfavorable. Select None and enter 0 for no effect (i.e., zero variance).) Overhead spending variance Overhead volume variance $ 6,700 Favorable Unfavorable