5
Connect them with gears and they will run at the same speed - any sensor / control will have an accuracy range
2
You want something called a gearmotor, which is a modestly-sized DC motor that can run in either direction at a variety of speeds, depending on the voltage you feed it. You select the appropriate gear ratio to yield the RPM you want. See the Marlin P. Jones & Associates on-line catalog for a good selection of inexpensive gearmotors.
Also note that it is ...
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