Which of the following statements about the interaction of earth’s systems is true?
a.
the interaction between earth’s systems is limited to a response to human activity.
b.
the earth’s system interact using positive feedback only.
c.
the earth’s systems interact using negative feedback only.
d.
all of the earth’s systems interact with each other.

Needed fast 15 points the process of natural selection favors certain characteristics in organisms, while it selects against other characteristics. what would happen if there was zero variation between all of the organisms on earth? a.organisms would evolve to increase variety b.natural selection would operate faster c.less food would be available d.evolution through natural selection would not occur

What causes the cyclical changes in the appearance of the moon?

This map shows the member states of the european union (eu). based on this map, what is the most likely reason the eu was formed? a) to increase trade between european nations b) to protect themselves from foreign enemies c) to begin the process of forming one large nation d) to isolate europe from the rest of the international community j