Ignoring capacitive effects, what is the impedance of a 100 mH coil with an internal resistance of 45 ohms in parallel with a 4700 ohm resistor at a frequency of 500 Hz

Apulley system is used to lift a 2,000 newton engine up a distance of 3 meters. the operator must apply a force of 250 newtons to the chain of the pulley system to lift the motor. to lift the engine 3 meters, the operator must pull a total of 30 meters of chain through the pulley system. what is the value of di?