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1 The operator moved the brake valve to “_____________” when he saw a car on the track. 2 Before the ______________________ was installed, the train had too many wires. 3 Air brakes tend to have a long ___________________ in applying the brake to all cars. 4 Put the driver’s brake valve on “______________________”to stop the train. 5 ___________________ don’t replace air brakes completely; they just improve them. 6 Even a system that is ______________________ can have problems. 7 Electronic brakes eliminate ______________________ , so all of the cars slow down at the same time and speed.