a$.$ In cell I$21$ create a formula that quantifies the portion of the overall activity variance that is caused solely by the fact that The Munchkin Theatre actually put on four productions instead of the planned number of five productions. What is the amount in cell I$21?$

b$.$ In cell I$22$ create a formula that quantifies the portion of the overall activity variance that is caused solely by the fact that The Munchkin Theatre actually put on $64$ performances instead of the planned number of $60$ performances. What is the amount in cell I$22?$

c$.$ Create IF$-$THEN statements in cells J$21$ and J$22$ that properly label your variances in cells I$21$ and I$22$ as favorable $($F$)$ or unfavorable $($U$).$