The united states trade deficit first became a problem in the 1970s because _____.

The __________ are nomadic hunter-gatherers who inhabit the kalahari desert.

The suns absolute magnitude is described as _______ in comparison to other stars.

Unlike a volcanic mountain, a batholith forms from magma that _____.

When land has been overfarmed or overgrazed, _______ occurs.

The nigerian letter scam is an example of ________.

The ____ is defined as the total rate of change in a population's size per unit of time.

The __________ people are the earliest known inhabitants of africa's mediterranean coast.

Limestone and marble weather faster than granite because ________.

The thermosphere has _____ air pressure than the mesosphere.

The mass extinction at the end of the mesozoic era was caused by ______.