1) The world's largest volcano, Mauna Loa in Hawaii, is also one of the most active.

2) The eye of a cyclone is a region of calm, relatively clear skies and light winds at the center of the storm.

3) The ozone layer, located in the Earth's stratosphere, protects us from harmful ultraviolet (UV) radiation.

4) The fastest land animal is the cheetah, capable of reaching speeds up to 70 miles per hour (113 kilometers per hour) in short bursts.