After creating her standard curve for absorption versus the concentration (M) of FD&C Red 40 and processing her data, Sally found that her drinking strength Kool-Aid sample had a concentration of 6.163 x 10-⁶ M. If 0.248 grams of Kool-Aid powder was used to prepare an 8-fl oz cup of her assigned flavor, What is the percent by mass of FD&C Red 40 in her Kool-aid powder?