A pencil "lead" is actually made of graphite. Graphite is
made exclusively of carbon atoms.

compuond

Explanation:

It is: Element AND Pure Substance

Explanation:

"Since graphite is made up solely of a single element, it is neither a mixture nor a compound. To call graphite an element would sound strange, since the element is carbon, hence a more accurate term would be allotrope of the element carbon."

(You better do good on that test since you're...you know :D)

i believe you are right for all except the 3rd ( look at sqdancefan his answer is much better)

i believe that it is a exoplanet