Calculate the NPV of the following cash flows: you invest $3,000 today and receive $300 one year from now, $700 two years from now, and $1,100 starting four years from now. Assume that the interest rate is 7%._________计算以下现金流量的净现值:您今天投资3,000美元,从现在开始每年获得300美元,从现在开始两年获得700美元,从现在开始四年获得1,100美元。假设利率为7%。________