The unit of acceleration would be m/s² :)
Explanation:
Th electric force between charges is inversely proportional to the square of distance between them. It means,

Initial distance, r₁ = 2 cm
Final distance, r₂ = 0.25 cm
Initial force, F₁ = 1 N
We need to find the electric force between charges if the new separation of 0.25 cm. So,

So, the new force is 64 N if the separation between charges is 64 N.
I’m guessing it’s the last one, trough
The answer is A because it is an example of red shift which if basically the Doppler effect , but for light. The wavelength gets longer because it has visible light has shifted into the red end of the spectrum, showing that it has a shorter frequency with a longer wavelength; meaning it is moving away from us
I would think something like fire or a torch because that seems like it means heat or maybe a campfire picture