The marketing manager of a large supermarket chain would like to use shelf space to predict the sales of pet food.For a random sample of 12 similar stores, she gathered the following information regarding the shelf space, in feet, devoted to pet food and the weekly sales in hundreds of dollars..

Store	1	2	3	4	5	6
Shelf Space	5	5	5	10	10	10
Weekly Sales	1.6	2.2	1.4	1.9	2.4	2.6

Store	7	8	9	10	11	12
Shelf Space	15	15	15	20	20	20
Weekly Sales	2.3	2.7	2.8	2.6	2.9	3.1

Compute the value of the sample correlation coefficient between weekly sales and shelf space.