According to the textbook (Financial Management, 16 Ed., ISBN: 978-1-337-90260-1), Figure 6-6 in chapter 6 shows that investors can lower the investment risk of individual stocks by investing in diversified portfolios of at least 40 stocks from different industries. Similarly, chapter 6 (see figure on page 265) also suggests that long-term investors can reduce investment risks even further by allocating part of their money to international stocks. Explain the following: (a) What particular risks of individual stocks are lowered by holding diversified portfolios rather than investing in a single stock; (b) How much risk of a single stock can be eliminated on average by holding that stock in a diversified portfolio; and (c) Why would a portfolio that includes both domestic and international stocks has on average lower risk in the long run than a purely domestic diversified stock portfolio.