Calculate the formula mass of each compound. Keep at least one decimal place in atomic masses from the periodic table.
H2S and HBrO4

acid rain does not usually kill trees directly. instead, it is more likely to weaken the trees by damaging their leaves, limiting the nutrients available to them, or poisoning them with toxic substances slowly released from the soil. the main atmospheric pollutants that affect trees are nitrates and sulphates.

the answer to this question is 3.