Answer:
The concentration of antibiotic after 4 hours will be 11.04 ppm (parts per million).
Explanation:
Given that the concentration of antibiotics after h hours can be given by the polynomial:
-0.06h^2+2h+4=A(h)
For h=4, equation will be:
-0.06 (4)² + 2 (4)+4= A (4)
11.04 = A (4)
The concentration of antibiotic after 4 hours will be 11.04 ppm (parts per million).