A school office needs to buy two new copiers, R and S, and can spend no more than $10,000. Each copier will...

A school office needs to buy two new copiers, R and S, and can spend no more than $10,000. Each copier will cost at least $3,000, and copier S will cost at least twice as much as copier R. Let R and S be the costs, in dollars, of the copiers.
Which system models the conditions, and which purchase meets all of them?
A. R + S ≤ 10,000; S ≥ 2R; R ≥ 3,000. Copier R costs $3,000 and copier S costs $7,000.
B. R + S ≤ 10,000; S ≥ 2R; R ≥ 3,000. Copier R costs $3,500 and copier S costs $6,500.
C. R + S ≤ 10,000; R ≥ S; R ≥ 3,000. Copier R costs $7,000 and copier S costs $3,000.
D. R + S ≥ 10,000; S ≥ 3,000; S ≥ 3,000. Copier R costs $4,000 and copier S costs $8,000.