题目大概意思是：
The corporate bond currently yields 4.90%.
用risk premium approach,算出Required yield = Real risk-free interest rate + Inflation premium + Default risk premium + Maturity premium + Call risk premium= 1.30% + 1.50% + 0.80% + 1.00% + 0.60%= 5.20%
问：should purchase the corporate bond？
答案：The bond should not be purchased because the market yield of 4.90% does not fully compensate for the risks embedded in the bond.
可我认为，买入bond在于未来yield的上升，current market yield应该上升并等于Required yield，这是对的莫？
