C28: A container is filled with oil and fitted on both ends with pistons. The area of the left piston is 10 mm2; that of the right piston 10,000 mm2. What force must be exerted on the left piston to keep the 10,000-N car on the right at the same height?

1. 10 N

2. 100 N

3. 10,000 N

4. 106 N

5. 108 N

6. insufficient information