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4-49. Consider the accompanying cash-flow diagram. (See Figure P4-49.)(4.7) a. If P=$1,000,A=$200, and i%=12% per year, then N= ? b. If P=$1,000,A=$200, and N=10 years, then i= ? c. If A=$200,i%=12% per year, and N=5 years, then P= ? d. If P=$1,000,i%=12% per year, and N=5 years, then A=