Final answer:
The complete question represented by c̄ is 'What is the speed of light?'
Step-by-step explanation:
The complete question represented by c̄ is 'What is the speed of light?' The symbol c represents the speed of light.
To find the complete question, we need to identify the known and unknown variables. In this case, c is known as the speed of light, and the unknown is the question itself, which asks for the speed of light.
So the complete question represented by c̄ is 'What is the speed of light?'