Answer:
a)
Step-by-step explanation:
Cost function = revenue function - profit function
= -0.3x² + 150x - [-0.5x² + 250x - 300]
= -0.3x² + 150x + 0.5x² - 250x +300
= -0.3x² + 0.5x² + 150x - 250x + 300 {Combine like terms}
= 0.2x² - 100x + 300
