The of a stream, or its channel slope, is the steepness with which it descends from its highest elevation to its lowest - expressed in feet per mile of meters per kilometer.

Based on their location in the atmosphere, the layers are able to have their own special characteristics. for example, most weather occurs in the troposphere. what occurs in each of the other layers?

Write a 150-word essay describing the effect of people's activities on the environment in the region.

Which of the following can scientists estimate geologic time? a.observing rock sequences b.radiometric dating c.comparing fossils d.all of these