11.50 A liquor wholesaler is interested in assessing the effect of the price of a premium scotch whiskey on the quantity sold. The results in the accompanying table on price, in dollars, and sales, in cases, were obtained from a sample of 8 weeks of sales records.

Price 19.2 20.5 19.7 21.3 20.8 19.9 17.8 17.2 Sales 25.4 14.7 18.6 11.4 11.1 15.7 29.2 35.2 Test, at the 5% level against the appropriate one-sided alternative, the null hypothesis that sales do not depend linearly on price for this premium scotch whiskey.