Question: A survey of 144 retail stores revealed that the average price of a DVD was $375 with a standard error of $20. What is the 99% confidence interval to estimate the true cost of the DVD?
A) $323.40 to $426.60
B) $328.40 to $421.60
C) $335.00 to $415.00
D) $335.80 to $414.20