The figure below depicts a 0-to-10 potentiometer as a variable load resistor connected to a circuit of an unknown architecture. When the wiper position on the potentiometer was adjusted such that , the current through it was measured to be 3 mA, and when the wiper was lowered so that , the current decreased to 2.5 mA. Determine the value of that would extract maximum power from the circuit.

A2-m rigid tank initially contains saturated water vapor at 100 kpa. the tank is connected to a supply line through a valve. steam is flowing in the supply line at 600 kpa and 300 c. the valve is opened, and steam is allowed to enter the tank until the pressure in the tank reaches the line pressure, at which point the valve is closed. a thermometer placed in the tank indicates that the temperature at the final state is 200°c. determine (a) the mass of steam that has entered the tank (b) the amount of heat transfer.