1.  Suppose we’re testing a new antibacterial cream, “Formulation NS,” on a small cut made on the inner forearm.  We know from previous research that with no medication, the mean healing time (defined as the time for the scab to fall off) is 7.6 days, with a population standard deviation 1.4 days.  The claim we want to test here is that Formulation NS speeds healing (decreases the time). 

Procedure:  We cut 25 volunteer college students and apply Formulation NS to the wound.  The mean healing time for these subjects is 7.1 days.  We assume that sigma = 1.4 days.

a.  What type of test is this and why?
b.  Assuming all assumptions are met, and using the Computer printout, make a conclusion.  State your answer like you would in step 5 of the 5-step procedure (No! you do not need to do all 5 steps).
c.  Write the probability statement and notation that would lead to the p-value given in the Minitab output.
d.  Suppose the researcher chose a 1% level of significance opposed to the regular 5%.  Explain why the conclusion would be different.

2.  The heart rate of a healthy lion is approximately normally distributed with mean mu = 40 beats per minute.  A heart rate that is too slow or too fast can indicate a health problem.  A veterinarian has removed an abscessed tooth from a young, healthy zoo lion.  As the animal slowly starts to come out of the anesthetic, the heart rate is taken and recorded for half an hour to see if the heart rate is too slow or too fast.  The following data are recorded (beats per minute):
[30, 37, 43, 38, 35, 36]

a.  Why must we employ the “t-test’ here? 
b.  Calculate the t-score.
c.  State the hypothesis as a question?
d.  Is there reason to be concerned for the lion’s health?  Answer simply and then justify your answer by writing a conclusion as you would in step 5 of the 5-step hypothesis procedure (all assumptions are met)
e. Show the notation and work that leads to the appropriate p-value.