What does the suffix -logy most likely mean?

Familial hypercholesterolemia, an autosomal dominant disease, is five times more frequent in the afrikaner population of south africa than in the original population of europe from which the ancestors to the afrikaners immigrated. what does this demonstrate?

Liquid water turns into water vapor at which step in the water cycle

Ais a landform that is formed at the mouth of a river from the deposition of sediment carried by the river as the water flows.