A monkey has a robotic arm connected to its brain using a Bluetooth transmitter. The arm requires a current of 400 run. If the arm has a resistance of 56 M Ohmswhat is the necessary voltage from a battery will it need to run?

An inventor claims to have developed a reversed heat engine (ie. a heat pump) which is able to deliver 10 kj heat into the room at 20°c from outside ambient temperature of -10°c by consuming only 2 kj electricity in winter. this claim is a)-impossible b)-possible only if the heat pump is ideal c)-practically possible d)-unable to be assessed as it depends on the working fluid used in the heat pump.