Please also show me the calculating process of the answer. Thank you!

Flag question QUESTION 3 Not complete Marked out of 4.00 Differential Analysis cost is as follows (parentheses indicate decreases): In each of four independent cases, the amount of differential revenue or differential 2 Increases (decreases) in: Revenue Costs $18,000 $0 ? ?$(12000) $0 For each case, determine the missing amount that would be necessary for the net differential amount to be: a. $10,000 Use a negative signs with answers to reflect decreases. 2 Increases (decreaes) in: Revenue $18,000 s0 $ Costs $(12,000) so b. ($6,000) Use a negative signs with answers to reflect decreases. 2 Increases (decreases)