CH4 is the molecular formula for methane.
Answer:
B.
Explanation:
Elemental analysis involves the actual percentage compositions of each element in the sample of the compounds. We know that there are two different compounds here that both contain copper and oxygen. What we don't know is the actual number of copper or oxygen composed in the compounds.
An elemental composition of these compounds would thus tell us this and will give an idea of the chemical formula of each since we now know quite well the percentage composition of each of these elements
The controlled variable is what he eats, the dependent variable is his weight.
a word of advice for your next ask, try to use better grammar and punctuation because this was kinda hard to follow.