Ted and carol are planning to provide for their 2 daughters future college tuition. The oldest daughter is expected to need $8000 in 8 years, $9000 in 9 years, $10000 in 10 years and $11000 in 11 years. The youngest daughter is expected to need $14000 in 14 years, $15000 in 15 years, $16000 in 16 years and $17000 in 17 years. If ted and carol can earn 8 percent annually, what single amount do they need to invest today to provide for their daughters future college tuition?