Copper Plate Distortion Problem

An experiment was conducted on the warping of copper plates. The two factors used in the study are temperature and copper content of the plate. The dependent variable $($response$)$ is the degree of warping, and the data is as follows.

$\backslash$table$[[,,$Copper,Content $(\%),],[$Temperature $(C),40,60,80,100],[50,17,20,16,21,24,22,28,27],[75,12,9,18,13,17,12,27,31],[100,16,12,18,21,25,23,30,23],[125,21,17,23,21,23,22,29,31]]$

At $=0\mathrm{.}05,$ is there evidence that each factor affects warping? Is there an interaction between the factors?Evaluate the residuals of this experiment.

Calculate the average warping at each level of copper content, and if lower warping is preferred, what level of copper content is appropriate?

If it is assumed that temperature is not easy to control in the environment where the copper plate is used, does the answer to $3)$ change?