A negative feedback mechanism works by opposing variations in conditions. This feedback mechanism tries to negate changes to restore the equilibrium of a system. A neutral feedback mechanism supports a change that occurs in the value of a parameter.

people flirt to show their affection towards someone in a less forward way then telling. they want the other person to guess what they’re feeling to have the other person also start to like them

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.

i'm pretty sure its b i might be wrong though!