थेवेनिन और नॉर्टन के प्रमेय केवल किस प्रकार के सर्किट पर लागू होते हैं?

While calculating Thevenin resistance (Rth) or Norton resistance (RN), independent constant current sources in the circuit are:

While calculating Thevenin resistance (Rth), constant current sources in the circuit are:

According to the Maximum Power Transfer Theorem, maximum power is delivered from a source to a load when the load resistance (RL) is equal to the internal resistance (r) of the source. At this specific condition, what is the efficiency of the power transfer?