The standard mean length of a bar must be 43 inches.  A sample of
current production indicates the following lengths:  42, 39, 42, 45,
43, 40, 39, 41, 40, 42, 43, 42, where s=1.78 and xbar=41.5.  Perform a
t test to determine if the production meets the standard.  Answer the
following:
7.	H0.
8.	H1.
9.	t Critical.
10.	t Calculated.
11.	Decision.
12.	Explanation of Decision