An entrepreneur is considering the purchase of a coin-operated laundry. The current owner claims that over the past 5 years, the average daily revenue was $675 with a standard deviation of $75. A sample of 30 days reveals daily average revenue of $625. If you were to test the null hypothesis that the daily average revenue was $675 and decide not to reject the null hypothesis, what can you conclude?
a) There is not enough evidence to conclude that the daily average revenue was $675.
b) There is not enough evidence to conclude that the daily average revenue was not $675.
c) There is enough evidence to conclude that the daily average revenue was $675.
d) There is enough evidence to conclude that the daily average revenue was not $675.