In parasitism, one organism harms another organism (the host). An example would be fleas living in cats/dogs; they feed on their blood.
Therefore the answer is A is harmed, and B is helped.
Phylum. The classification system goes: Kingdom, Phylum, Class, Order, Family, Genus, Species. Anything that shares a class also share anything above it.
It takes 27 days for the moon to orbit the earth
The population of the mice would most likely increase. This is because the number of predators of mice will decrease. Predators are those that feed on others, in this case mice. When predators decrease, the prey (which would be the mice) will be able to populate thus leading to an increase in population.
