In a Hypothesis Test for Means, a sample size of 20 has produced a Mean of 9.5 mm with a Standard Deviation of 0.5 mm. The customer specification on the part is 10 mm.
At 5% significance level, what should the customer do?
A . Reject the lot
B . Accept the lot
C . State the population Mean is greater than 10 mm
D . Change their specification to 9.5 mm
Answer: B