Questions

We know that All compounds are molecules, but not all molecules are compounds.

Water is a molecule because it is made from atoms that have been chemically combined. It is also a compound because the atoms that make water are not all the same - some are oxygen and some are hydrogen.

Hence, Water is a molecule and a compound.

For an atom to emit X-rays it should have difference in energy levels

The Quick Brown Fox Jumped Over The Lazy Dog  is the sentence which contains all 26 alphabets i.e, from a to z.

A resource is a source or supply from which a benefit is produced. Resources can be broadly classified upon their availability they are renewable and non renewable resources.

Renewable Resources :: A resource that can be replenished after use are known as Renewable resources.

Examples :: Sunlight, Water, biomass,...

Non renewable Resources :: A resource that, once used, is no longer available are known as Non renewable Resources. 

Example :: Coal, fossil fuels, natural gas,...

Sunlight is the both renewable and inexpensive resource from the given options.

The letter 'E'.

As of the above given data,

It is in the 1st place in Earth, 2nd in Heaven and in the middle of the Sea.

It appears once in a Year and twice in a Week.

It is present in February, June, September, October, November & December.

But not in the Month.

Hence, it is the letter 'E'.