Indicate which of the following choices best identifies the hypothesis test. a. independent group means, population standard deviations and/or variances unknown
b. matched or paired samples
c. single mean
d. two proportions
e. single proportion

A powder diet is tested on 49 people, and a liquid diet is tested on 36 different people. The population standard deviations are two pounds and three pounds, respectively. Of interest is whether the liquid diet yields a higher mean weight loss than the powder diet.