单选题Running an electric winch at slow speed over a long period of time causes（）.Athe speed to be retarded by the friction brakeBa load to go downward at full speedCthe circuit breaker to turn offDthe resistors to overheat and eventually burn out
单选题
Running an electric winch at slow speed over a long period of time causes（）.
A
the speed to be retarded by the friction brake
B
a load to go downward at full speed
C
the circuit breaker to turn off
D
the resistors to overheat and eventually burn out
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