A polling organization polls n = 400 randomly selected registered voters to estimate the proportion of a large population that intends to vote for Candidate Y in an upcoming election. Although it is...

(a) Give the numerical value of the mean of the sampling distribution of p̂.
Mean =



(b) Calculate the standard deviation, s.d., of the sampling distribution of p̂. (Round your answer to the nearest hundredth.)
s.d. =



(c) Use the Empirical Rule to find values that fill in the blanks in the following sentence. (Round all answers to the nearest hundredth.)
In about 99.7% of all randomly selected samples of
n
= 400 from this population, the sample proportion preferring Candidate Y will be between and .