1.
_____________________ is a gas composed of carbon and oxygen.
2.
Fuels such as coal, oil, and natural gas are known as _______________________.
3.
______________________ means using natural resources in a way that they will exist for future generations.
4.
______________________ are substances that are discharged into the air.
5.
The process by which farmland becomes less productive because the land is degraded is called __________________________.
6.
An increase in the average temperature of the Earth's atmosphere is called ________________________.
7.
The time during the year when the sun reaches the furtherest northern or southern point in the sky is called the ______________________.
8.
A ___________________ has plants that are specially adapted to dry conditions.
9.
Rain, snow, sleet or hail are known as ________________________.
10.
A _______________________ is a region where plants are usually a mix of grasslands and scattered trees.
11.
Typical weather conditions of a region over a long period of time is called _________________.
12.
An ____________________ is when the days and nights are of equal lengths and the sun is directly over the equator.
13.
The _____________________ is the layer of gasses that surround the earth.
14.
Water found beneath the earth's surface is called _______________________.
15.
The area drained by a major river is called a ______________________.
16.
A feature on the earth's surface formed by a physical force is known as a ___________________.
17.
A _____________________ is a broad, flat area of land higher than the surrounding land.
18.
The circulation of water between the Earth, oceans, and atmosphere is called the _______________________.
19.
A ______________________ is an opening in the Earth's crust from which magma, ash, and hot gasses flow.
20.
_________________ is molten rock.
21.
Pieces of rock in the form of sand, silt, and stone deposited by erosion are ____________________.
22.
One of seven large landmasses on the Earth's surface is called a ______________________.
23.
A zone of volcanoes around the Pacific Ocean is known as the _______________________.
24.
A __________________________ is a large, rigid section of the earth's crust that is in constant motion.