You are designing a research project in which you will compare the proportions of two groups of guinea pigs (Abyssinian and Teddy) for their incidence of urinary calculi. You would like the power (sensitivity) of the experiment to be 90%, and you have set the alpha to 0.05. What is the value of C, and which formula would you use to determine the smallest sample size needed per group?

Group of answer choices, choose one.

• C = 7.8, n = 2*C*Pav*(1-Pav)/w2

• C=10.5, n = 2*C*Pav*(1-Pav)/(s/w)2

• C = 10.5, n = 2*C*(s/w)2

• C = 7.8, n = 2*C*(s/w)2

• C = 10.5, n = 2*C*Pav*(1-Pav)/w2