Recently, Yahoo Finance reported the following market betas for the stocks of selected healthcare providers listed below:

Company	Beta
Quorum Health Corporation (QHC)	1.86
HCA Healthcare, Inc. (HCA)	1.14
UnitedHealth Group Incorporated (UNH	0.88
Johnson & Johnson (JNJ)	0.31

At the time these betas were developed, reasonable estimates for the risk-free rate and required rate of return on the market were 4 percent and 12 percent respectively.

a. What are the required rates of return on the four stocks? (Complete the following table)

Company	Required rates of return
Quorum Health Corporation (QHC)
HCA Healthcare, Inc. (HCA)
UnitedHealth Group Incorporated (UNH
Johnson & Johnson (JNJ)

b. Why do their required rates of return differ?

c. Suppose that a person is planning to invest in only one stock rather than a well-diversified stock portfolio. Are the required rates of return calculated above applicable to the investment? Please explain.