Your answer is............4x3 - 14x + 24 square centimeters
Y = -2x^2 + 50x + 300
-2x^2 + 50x + 300 ≥ 300
-2x^2 + 50x ≥ 0
-2x^2 ≥ -50x
x^2 ≤ 25x
x ≤ 25
Therefore, required domain is 0 ≤ x ≤ 25
D, because we already know how much he spent in total so it isnt B, trust me its D