1. The number of miles of useful tread wear (in 1000s) was determined for tires of each of five different makes of subcompact car (factor A, with I
5) in combination with each of four different brands of radial tires (factor B, with J
4), resulting in IJ
20 observations. The values SSA
30.6, SSB
44.1, and SSE
59.2 were then computed. Assume that an additive model is appropriate.

a. Test H0: 1
2
3
4
5
0 (no differences in true average tire lifetime due to makes of cars) versus Ha:

at least one i 0 using a level .05 test.

b. H0:
1

2

3

4
0 (no differences in true average tire lifetime due to brands of tires) versus Ha: at least one
j 0 using a level .05 test.