34. Refer to the MINITAB output of Exercise 20, in which x
NO

3 wet deposition and y
lichen N (%).

a. Carry out the model utility test at level .01, using the rejection region approach.

b. Repeat part

(a) using the P-value approach.

c. Suppose it had previously been believed that when NO

3 wet deposition increases by .1 g N/m2

, the associated change in expected lichen N is at least .15%. Carry out a test of hypotheses at level .01 to decide whether the data contradicts this prior belief.