68290
Since the net flow of electromagnetic energy is given by the average Poynting vector , this means that the Poynting vector in these regions , as averaged over a complete oscillation cycle , is zero .
 Poynting, Poynting
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: location, person, organization 
Text: {0} 
Answer:
 Poynting, Poynting