This is a question that i couldn't solve from a bunch of questions if
you could help me in this it would be great.
    A health spa claims that a new exercise program will reduce a
persons waist size by 2 cm over a 5 day period.  the waist sizes of 6
men were recorded before and after the 5th day period in the following
table:
MAN     1     2     3     4      5      6
--------------------------------------------
BEFORE  90.4  95.5  98.7  115.9  104.0  85.6
AFTER   91.7  93.9  97.4  112.8  101.3  84.0

A) Test the hypothesis that the variances of the before and after
groups are the same .  Use the 0.05 level.

B) Test the null Hypothesis u1=u2 vs. u1>u2 at the 0.01 level.  do
this in two ways:
1) the variance of the two groups are equal but unknown.
2) use paired observations.

C) Test the null hypothesis u1-u2=2 vs. u1-u2 doesn't equal 2at the
0.05 level.  do this in two ways:
1) The variances of the two groups are equal but unknown.
2) use paired obdervations.