2. assume that the population proportion of adults who smoke cigarettes is 0.42. a random sample of 300 adults is to be selected to test this claim. a) what is the shape, mean, and standard deviation of the sampling distribution of the sample proportion for samples of 300? b) what is the probability that the sample proportion will be less than 0.50? c) what is the probability that the sample proportion will fall within 3 percentage points( /- 0.03) of the population proportion?