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