The supply and demand curves for a product are given by functions S and D, respectively. For a given number of units, Q, S is the minimum price, in dollars, that the supplier should accept. D is the maximum price, in dollars, where consumers will purchase that number of units S(Q) = 45 + 0.040
KD(Q) = 110-0.0030

For the above equations, which of the following combinations of price and quantity fall between the maximum consumer price and minimum supplier price?

a. 500 units at $105
b. 1,000 units at $80
c. 1,500 units at $110
d. 2,450 units at $110