The speed of light is around 3.000E5 km/s. It takes approximately 9.221 seconds for light reflected from the moon Vega to reach planet Xartan. What is the average distance from the moon Vega to the planet Xartan?

The electric field between square plates of a parallel-plate capacitor has magnitude e. the potential across the plates is maintained with constant voltage by a battery as they are pulled apart to twice their original separation, which is small compared to the dimensions of the plates. the magnitude of the electric field between the plates is now equal to a)e b)e/4 c)e/2 d)4e e)2e