A random sample of 802 supermarket shoppers determined that 378 shoppers preferred generic-brand items. Test at the 10% level the null hypothesis that at least one-half of all shoppers preferred...

A random sample of 802 supermarket shoppers determined that 378 shoppers preferred generic-brand items. Test at the 10% level the null hypothesis that at least one-half of all shoppers preferred generic brand items against the alternative that the population proportion is less than one-half. Find the power of a 10%-level test if, in fact, 45% of the supermarket shop- pers preferred generic brands.