19.2 centimeters
Explanation: Convert 4m 8cm into cm so it is 408cm. Divide 408 by 10 and you get 40.8cm. Then divide 540 by 9 and you get 60cm. 40.8 and 60 are the measurements of each piece of wire. Subtract 40.8cm from 60cm to get 19.2cm which is the answer.
