For questions 1 through 20. read each question carefully. choose the best answer for each question or statement.
1. which of the following is true about population pyramids? (1 point)
a. they express the ages and salary ranges of a group of people.
b. they express the ages and population numbers of a group of people.
c. they highlight changes in the push-pull factors of a population.
d. they demonstrate race-related information about a group of people.

The answer is b.

Explanation:

Population pyramids is a graph that shows the number of people in each age range of a population. Each level of the graph moves up by 5 years, typically. 0-15 is considered young dependants, 15-64 is considered economically active and 65+ is considered elderly dependant. The graph is grouped into male and female. It is more common to see the male column on the left and the female on the right.

doctrine that the us had the right to expand throughout north america.