I need an explanation how to do the below question please .

Emil Manufacturing incurs unit costs of $7.00 ($5.00 variable and $2.00 fixed) in making a sub-assembly part for its finished product. A supplier offers to make 18,900 of the parts for $5.60 per unit. If it accepts the offer, Emil will save all variable costs and $1 of fixed costs. Prepare an analysis showing the total cost savings, if any, that Emil will realize by buying the part. (Round per unit answers to 2 decimal places, e.g. 15.25. If an amount reduces the net income then enter with a negative sign preceding the number, e.g. -15,000 or parenthesis, e.g. (15,000).) Net Income Increase (Decrease) Per Unit Make Buy Number of units: 18900 Variable manufacturing costs 94500 -94500 $ Fixed manufacturing costs 37800 37800 Purchase price 105840 105840 132300 Total annual cost 143649 $ The decision should be to