The cash-flow diagram is provided. a. If P=$1,000,A=$250, and i%=15% per year, then N= ? b. If P=$1,000,A=$250, and N=10 years, then i= ? c. If A=$250,1%=15% per year, and N=5 years, then P= ? d. If P=$1,000,i%=15% per year, and N=5 years, then A= ? Consider the accompanying cash-flow diagram. P| A/year End of Year Interest =i%/ year