The officers of a high school senior class are planning to rent buses and vans for a class trip. Each bus can transport 70 students, requires 6 chaperones, and costs $1,000 to rent. Each van can transport 10 students, requires 1 chaperone, and costs $100 to rent. Since there are 980 students in the senior class that may be eligible to go on the trip, the officers must plan to accommodate at least 980 students. Since only 90 parents have volunteered to serve as chaperones, the officers must plan to use at most 90 chaperones. How many vehicles of each type should the officers rent in order to minimize the transportation costs? What are the minimal transportation costs?

The officers should rent _ buses and _ vans to minimize the transportation costs.

The minimal transportation costs are $_.