=+different coarse aggregate contents (%), with two observations made for each such combination, resulting in the conductivity data (W/m•K) given here:

Coarse Aggregate Content (%)

38 41 44 Asphalt Binder Grade PG58 .835, .845 .822, .826 .785, .795 PG64 .855, .865 .832, .836 .790, .800 PG70 .815, .825 .800, .820 .770, .790

a. Test for the presence of interaction between the two factors. Use  5 .01.

b. Use  5 .01 to test the hypothesis that coarse aggregate content has no effect on thermal conductivity.

c. Use  5 .01 to test the hypothesis that asphalt binder grade has no effect on thermal conductivity.