Reintroduction of wildlife species means an attempt to resettle them within their historical area of distribution (within their range), where they have become extinct
2. includes evolution at the population and community level
4. refers to evolution above the species level
The appropriate answer is d. Dead plants in a swampy environment is the perfect environment for the beginning of the coal forming process. Over time layers pile up in this anaerobic environment. The plant or organic material gets buried overtime by dirt or rocks. Millions of years of burial will expose the matter to heat and pressure and will eventually lead to the formation of coal and other petroleum products.
Carbon dioxide increases acidity when dissolved in water e.g. in blood as it reacts with the water to form carbonic acid which has a slightly acidic pH.
