A metallurgy company wanted to investigate the effect of the percentage of ammonium and the stir rate on the density of the powder produced. The results are as follows: Stir Rate
Ammonium (%) 100 152
2 10.95 7.54
2 14.68 6.66
2 17.68 8.03
2 15.18 8.84
30 12.65 12.46
30 15.12 14.96
30 17.48 14.96
30 15.96 12.62
At the 0.05 level of significance:.
a. is there an interaction between the percentage of ammonium and the stir rate?
b. is there an effect due to the percentage of ammonium?
c. is there an effect due to the stir rate?
d. plot the mean density for each percentage of ammonium for each stri rate.