As the mass of the nucleus increases, what happens to the ratio of neutrons to protons in stable isotopes? A. The neutron:proton ratio decreases. B. The neutron:proton ratio increases. C. The neutron:proton ratio remains 1:1. D. The neutron:proton ratio remains 1.5:1.

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.

there are two significant figures.