In a metal fabrication process, metal rods are produced to a specified target length of 15 feet. Suppose that the lengths are normally distributed A quality control specialist collects a random sample of 16 rods and finds the sample mean length to be 14.8 feet and a standard deviation of 0.65 feet. Which of the following statement is true?
a. The sampling distribution of the sample mean follows the t- distribution with 15 degrees of freedom.
b. The sampling distribution of the sample mean follows the t- distribution with 16 degrees of freedom.
c. The standard error is 0.65 feet.
d. The sampling distribution for the sample mean is Normal with a mean of 14.8 feet and standard deviation of 0.65 feet.
e. The mean of the sampling distribution for the sample mean is 14.8 feet.