Yоu wоuld like tо study the effect of а new drug on humаn breаst cancer, using mice. You culture the human tumor cells in vitro, and then inject them subcutaneously (directly under the skin) into immunodeficient mice. a. Why is an immunodeficient mouse needed for this experiment? b. What are two advantages of this type of experiment? c. What are four disadvantages of this type of experiment?