How much invested now at i= 7% would be enough to provide three payments, with the first payment in the amount of $8400 occurring two years hence (count from time zero), then $6800 five years hence (count from time zero), $5000 seven years hence (count from time zero)? (Please keep the integer)

How much invested now at i=7% would be enough to provide three payments, with the first payment in the amount of $8400 occurring two years hence (count from time zero), then $6800 five years hence (count from time zero), $5000 seven years hence (count from time zero)? (Please keep the integer)