Answer:
last one
they can contain mercury that is Very harmful to humans
Answer:
H2O2
Explanation:
2 hydrogen, 2 oxygen wikipedia it
If u want the real answer go to answers.com
Answer:
a
Explanation:
A Gamma rays is the best wavelength for an astronomer to use to study the composition of planets and stars
<span>the theory that changes in the earth's crust during geological history have resulted chiefly from sudden violent and unusual events.
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