Draw and explain expanding age pyramids of human population. Why is it so called ?

Explanation

### Step-by-Step Solution:

1. **Understanding Age Pyramids**:
- An age pyramid is a graphical representation that shows the distribution of various age groups in a population. It is typically displayed as a bar graph with age groups on the vertical axis and the population percentage on the horizontal axis.

2. **Types of Age Pyramids**:
- There are three main types of age pyramids: expanding, stationary, and declining. Each type reflects the growth trends of a population.

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