You are presented with the quiz "Microbial fuel cells convert chemical energy into what?" 

But you don't know the answer, so you turn to your teacher to ask for hints. He says that "microbial fuel cells convert chemical energy into electrical energy" and "electrical energy can be converted into kinetic energy and heat energy by an electric motor". 

So, what's the best answer to the question?


 

       Something that can be converted to kinetic and heat energy by a motor    