Vitamin D is needed for the body to use calcium. An experiment is designed the effects of calcium and vitamin D supplements on the bones of first-year college students. The outcome measure is the total body mineral content (TBBMC), a measure of bone health. Three doses of calcium wil be used: 0, 200, and 400 mg/day. The doses of vitamin D will be 0, 50, and 100 international units (IU) per day. The calcium and vitamin D will be given in a single tablet. Al tablets including those with no calcium and no vitamin D will look identical. Subjects for the study will be 90 men and 90 women.

a) What are the factors and the treatments for this experiment?
b) Draw a picture explaining how you would randomize the 180 college students to the treatments
c) Use a spreadsheet to carry out the randomization