Answer:
25 minutes and 33 seconds
Step-by-step explanation:
please brainiest
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.
Z-4/9-1/3=5/9
z-4 =5/9(9-1/3)
z-4 =4.414814815
z =8.814
Depend on the time frame, A.M or P.M.