Lava and other materials that are launched from a volcano into the air are referred to as
a. basalts.
b. tephra.
c. flows.
d. magma.

Distance that the transcontinental railroad covered from omaha to san francisco.

Ozone in the upper atmosphere has been depleted by a. sulfur dioxide. b. chlorofluorocarbons. c. carbon dioxide. d. oxygen.

Look at the diagram showing the different wavelengths in sunlight. which statement describes electromagnetic waves with wavelengths greater than 700 nanometers? they take the form of heat. they can cause skin cancer and sunburn. they are some of the shortest waves. they can be seen by human eyes as visible light.