Are researchers who most often study a population, its people, and its trends.
a.
geologists
b.
demographers
c.
anthropologists
d.
historians

I believe the correct answer from the choices listed above is option B. Demographers are researchers who most often study a population, its people, and its trends.They  study subjects such as the geographical distribution of people, birth and death rates, socioeconomic status, and age and sex distributions in order to identify the influences on population growth, structure, and development.

It should be at the center of any map going vertically: the prime meridian, as it passes through greenwich,  england, is considered 0 degrees longitude