I want to know the answer to the following question:
What is a measure of the power of an antenna?
All the background I'm provided with is that "For instance, if a radio wave passing a given location has a flux of 1 pW / m2 (10−12 watts per square meter) and an antenna has an effective area of 12 m2, then the antenna would deliver 12 pW of RF power to the receiver (30 microvolts rms at 75 ohms).". Is that enough to answer the question?
Answer: yes