Jennifer, a teacher, and Wally, an IT professional have twin girls with special needs and as a result have on going medical expenses. Jennifer expects that her family medical cost for 2021 will be $35,000. She has a Blue Cross, Blue Shield PPO through her school district. Her family deductible is $3,500. The co-insurance is 80/20. Her plan Max out-of-pocket is $12,500 for the year. How much will BXBS cover? (Answer with a positive number, round to the nearest dollar)