5. The extinction coefficient determined above was for the mixture of Kool-Aid, which contains red dye 40, preservatives and flavoring agents. The actual extinction coefficient for Red 40, which causes most of the absorption, is 2.7 x 104 Lmol-1cm-1 around 500nm. Determine the concentration of red dye in the stock solution. This calculation requires you to determine the concentration of test tube 1 (the working solution) and then use the dilution factor to convert this concentration to that of the stock solution.