Surface tension is the property of water which allows for some lightweight insects to walk on top of a pond and not fall in. The molecules of water are held together by cohesive forces. The molecules of water present below the surface experience this cohesive force from all the directions, whereas the water molecules present on the surface experience a downward pull, as the force is not balanced. This leads to the concaving of the water surface inside a small tube.
The insects clustered around the light is an example of A response to a stimulus. The insects are attracted to the light, so the flocked towards it.
I believe it would be 780 million km.
5.2 AU times 150 million km.
hope this helps