Answer:

1. Biodiversity is important to humans for many reasons. Ecological life support— biodiversity provides functioning ecosystems that supply oxygen, clean air and water, pollination of plants, pest control, wastewater treatment and many ecosystem services.
2. Some examples of limiting factors are biotic, like food, mates, and competition with other organisms for resources. Others are abiotic, like space, temperature, altitude, and amount of sunlight available in an environment. Limiting factors are usually expressed as a lack of a particular resource.
3. The natural population change is calculated by births minus deaths and net migration is the number of immigrants (population moving into the country) minus the number of emigrants (population moving out of the country).