A school is looking to hire teachers and TA's to fill its staffing needs for its summer program at minimum cost. The average monthly salary of a teacher is $2400 and the average monthly salary of a TA is $1100. The program can accommodate up to 45 staff members and needs at least 30 to run properly. They must have at least 10 TA's and may have up to 3 TA's for every 2 teachers. How many teachers and TA's should the program hire to minimize costs? What is the minimum cost? Show work.