In an advertising study the researchers wanted to determine if there was a relationship between the per capita cost and the per capita revenue. The following variables were measured for a random sample of advertising programs:
xi = Cost of Advertisement, ÷ Number of Inquiries Received
yi = Revenue from Inquiries, ÷ Number of Inquiries Received
The sample data results are shown in the data file Advertising Revenue. Find the sample correlation and test, against a two-sided alternative, the null hypothesis that the population correlation is 0.