An airplane company is determining the difference in selling price if rows of first-class seats are added to a
new design. Using the average selling price of $1,000
per first-class seat, the total selling price for one new
row is
f(1) = 4,000r. Each row in first class eliminates two rows
of economy seats. Using the average selling price of
$150 per economy seat, the total price for each pair of
removed rows is e(r)= 1,800r.

Which is d(r) the profit or loss for adding r rows of first class seats?

A. D(r)=2,200r
B. D(r)=5,800r
C. D(r)=-2,200r
D. D(r)=-5,800r

HURRY TIMED