i need help in the questions in the pic

I am planning to run an experiment in which I need to match pairs of participating subjects on two variables: one is a qualitative variable (subject's gender) and the other is a quantitative variable (subject's weight). How can I do this? Oops, I forgot to mention that there's a third variable, and it's quantitative as well (subject's height). Will your method for the two variables gender and weight handle this three-variable case as well? Instructions: Answer three questions: 1. What is the technical name for this problem? 2. What method should the client use? Explain in simple language how and why the method works. Also explain how it might fail. 3. How can the client actually implement the method? (Will statistical packages do it? Is there a special computer program? Could it be done with paper and pencil? Suggest one workable way to get the randomization done.)