Answer:
Methane is a chemical compound with the molecular formula CH4. It is the main component in natural gas. Methane is considered the simplest of alkanes, compounds that consist only of hydrogen (H) and carbon (C) elements. Methane is an odorless, colorless, tasteless gas that is lighter than air.
Explanation:

28%
Explanation:
mass of solute(KBr) = 3.73g
mass of solvent(H2O) = 131g
mass of solution = mass of solute + mass of solvent
= 3.73 + 131
= 134.73g

The formula of the ppt. formed is PbSo4 , which is inslouble.
B. False
Stability is determined by the ratio of neutrons and protons. Electrons are not in nucleus.
Answer: The answer is the second one