I took this test and the correct answer is c
I hope this helps
Yes, C is correct. It self explains itself as we know light travels through a vacuum ( doesn't need a medium) and light is a type of electromagnetic wave.
The actual size of the Solar system is too big to show without making a much smaller model. If someone wants to see the orientation of the planets a model has to be made so we can see it without flying out too space.
Base in your questions that ask what cause the bright lines seen in the emission spectrum and i think the best answer to that is the H2 gas is used when protons was heated so the electron absorb all the photons and get exited and resulted by given of a light.
