ANOVA Table & Hypothesis Testing

The Buffalo, New York, cola distributor is featuring a super-special
sale on 12-packs.  She wonders where in the grocery store to place the
cola for maximum attention.  Should it be near the front door of the
grocery stores, in the cola section, at the checkout registers, or near
the mild and other dairy products?  Four stores with similar total
sales cooperated in an experiment.  In one store the 12-packs were
stacked near the front door, in another they were placed near the
checkout registers, and so on. Sales were checked at specified times in
each store for exactly four minutes.  The results were:

 

Cola at the Door In Soft Drink Section Near Registers Dairy Section

6 5 7 10

8 10 10 9

3 12 9 6

7 4 4 11

4 9 5 12

5 11 7 13

 

The Buffalo distributor wants to find out whether there is a difference
in the mean sales for cola stacked at the four locations in the store. 
Use an ANOVA analysis and the 0.05 significance level.