The level of elevation zone pyramid below that is labeled with the number one should be titled _. It represents the _ climate type.
A. Tierra helada . . . polar
B. Tierra templada . . . moderate
C. Tierra calienete . . . tropical
D. Tierra fria . . . dry

Seed plants that lived during the carboniferous impact life on earth today because a. they are the ancestors of all plant life on earth. b. their remains formed coal, which is an important resource. c. they produced fossils that are used to date many geologic events. d. their presence caused oxygen levels to drop, allowing animals to evolve.

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

What evidence does the writer give to support his argument about coral reefs? a) he speaks of the activities of coral polyps. b) he describes the composition of the great barrier reef. c) he emphasizes the ways in which coral reefs are fragile. d) he points out the ways that scientists do research on the reefs.