Arandom sample of 50 cars in the drive-thru of a popular fast food restaurant revealed an average bill of $18.21 per car. the population standard deviation is $5.92. round your answers to two decimal places.

(a) state the point estimate for the population mean cost of fast food bills at this restaurant $

(b) calculate the 95% margin of error. $

(c) state the 95% confidence interval for the population mean cost of fast food bills at this restaurant. $ ≤ µ ≤ $

(d) what sample size is needed if the error must not exceed $1.00? n =