I know one it is with matter
You can do a mixture by making a fruit salad
IBM and others are using copper instead of aluminum in the most powerful computer chips they manufacture. Because of copper's superior electrical conductivity, this technology enables conductor channel lengths and widths to be significantly reduced.
Answer: 2. cannot be an element.
Explanation:
Element is a pure substance which is composed of atoms of similar elements.It can not be decomposed into simpler constituents using chemical reactions.Example: Copper 
Compound is a pure substance which is made from atoms of different elements combined together in a fixed ratio by mass.It can be decomposed into simpler constituents using chemical reactions. Example: methane 

Thus as it can be decomposed into its constituent elements, it is a compound.
Mixture is a substance which has two or more components which do not combine chemically and do not have any fixed ratio in which they are present.
Thus methane cannot be an element.
I think It’s 55 but that’s just me
Tropic levels have most energy