Serendipity Cafe is thinking of expanding and opening a new location. It estimates the following expenses and profits for this multi-year project: Timeline Beginning of Year 1, or today In 1 year In 2 years In 3 years Cash flow -$7,500 3,000 6,400 6,900 a. At 0 percent required return, the NPV is b. At 13 percent required return, the NPV is instead c. At 19 percent required return, the NPV is instead d. At 24 percent required return, the NPV is instead