A. The term "units" refers to the measurements in the original question or problem. When looking at the question, the units we are measuring are dollars/feet.
B. In this case, the f'(x) means we are looking for the cost (in dollars) to drill the next foot down.
C. Since the cost increases the more feet we drill down, the sign of f'(x) is positive.
Answer:
25.5
Step-by-step explanation:
1530 divided by 60 is 25.5 and 25.5 multiplied by 60 is 1530.