Which of the following elements is the most reactive?

The colored discharge tubes used for advertising mainly contain .........

List the uses of Neon and argon gases.

Which of the following is employed in flash tubes in photography?

Given below are two statements:
Statement-$I$: Noble gases have very high boiling points.
Statement-$II$: Noble gases are monoatomic gases. They are held together by strong dispersion forces. Because of this,they are liquefied at very low temperatures. Hence,they have very high boiling points.
In the light of the above statements,choose the correct answer from the options given below:

Which noble gas was discovered first in the sun and then on the earth?