The sales of a Gnagey's Groceries average $8,000 per day. Gnagey introduced several advertising campaigns in order to increase sales. To determine whether or not the advertising campaigns have been effective in increasing sales, a sample of 55 days of sales was selected. It was found that the average was $8,240 per day with a sample standard deviation of $1,221. The null hypothesis is to be tested at 0.01 significance level.

What is the correct conclusion?

A. We accept the null hypothesis, and conclude that there is not a statistically significant increase in grocery sales

B. We cannot accept or reject the null hypothesis, we need to know the standard deviation in order to solve the problem

C. We fail to reject the null hypothesis, and conclude that there is a statistically significant increase in grocery sales

D. We cannot accept or reject the null hypothesis, we need to increase the sample size of the study

E. We fail to reject the null hypothesis, and conclude that there is not a statistically significant increase in grocery sales

F. We reject the null hypothesis, and conclude that there is a statistically significant increase in grocery sales

G. We reject the null hypothesis, and conclude that there is not a statistically significant increase in grocery sales

H. We accept the null hypothesis, and conclude that there is a statistically significant increase in grocery sales