Taxpayer, age 86 and single, redeems a Series EE U.S. savings bond during the current year. The bond redemption qualifies for the higher education exclusion. Taxpayer reports $80,000 of modified adjusted gross income for the year. The redemption produces a payment of $25,000, consisting of $5,000 interest and $20,000 return of principal. During the year, Taxpayer expended $22,000 for qualifying educational expenses for his dependent grandson . How much, if any, of the $5,000 interest should Taxpayer , exclude from gross income on his Form 1040 for the year