Which two factors increase the population size and population density?

Explanation

To answer the question regarding which two factors increase the population size and population density, we can break down the solution into clear steps:

### Step-by-Step Solution:

1. **Understanding Population Size and Density**:
- **Population Size** refers to the total number of individuals in a given population.
- **Population Density** is defined as the number of individuals per unit area or volume.

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