Answer:
<u>Definite</u> and <u>constant</u> composition
Explanation:
Examples of pure substances:
- table salt
- sugar (pure)
- water
- diamond
**sometimes, a pure substance is also called a chemical substance.
Answer:
they are concentrated
Explanation:
As the outer layer of your skin separates your body from its environment, the cell membrane (also known as the plasma membrane) separates the inner contents of a cell from its exterior environment.
Answer:
Rivers.
Explanation:
Most of Africa is covered with deserts and savannahs which are difficult to live in but rivers around the continent helped make sure cities and civilizations flourished.
The answer is The President is responsible for implementing and enforcing the laws written by Congress and, to that end, appoints the heads of the federal agencies, including the Cabinet. .The Cabinet and independent federal agencies are responsible for the day-to-day enforcement and administration of federal laws. The executive branch is responsible for enforcing the statutes enacted by the legislative branch. In the federal government, the executive branch is headed by the president of the United States.
