Complimentary colors—why does an object look a particular color to the human eye? specifically describe the copper solution and the colors that would be absorbed by that solution, and the same with the aspirin/iron solution.

When a sample absorbs light from a particular color, we recognize the object as the complementary color, if a sample absorbs red light, our eyes will see the sample appear blue-green.

Explanation:

Copper(II)  ion salts in aqueous ammonia produces a blue solution.  Copper(II) ion salts in aqueous hydrochloric acid produces a green solution.  Based on this evidence, The spectra of the two solutions will have different λmax values. if you add iron III salt to an aspirin you will see a purple color, it means that there is still some salicylic acid present and the sample is impure.

which statement about this sum is true? −245+2.7