Help me please will mark brainliest

of all of those x ray has the most energy.

visible light can travel significantly farther than x rays while they both work the same and travel at roughly the same speed .

and im not sure for the 3rd

Explanation:

hydrogen is a compound or a single element and a element is a pure substence that cannot be separated into simpler subtances

clorine is a compound its a chemical substance that forms when two or more different elements combine

so both hydrogen and clorine are compounds

the missing space is phylum