Ais something that is essential for an organisms life

The eruption of a nearby volcano causes a prairie ecosystem to receive a lot less sunlight.which of these is the most likely effect on the ecosystem? a-an increase in biodiversity. b-an increase in immigration to the area. c-a decrease in available water. d-a decrease in plant growth.

In which situations is the principle of cross-cutting relationship useful in determining relative age?

Most of the fossils found in virginia are in the coastal plain, valley, ridge, and appalachian plateau regions, best suggesting that these geographic provinces a) were once covered by seawater. b) are the oldest parts of virginia. c) have a great deal of karst topography. d) have large amounts of sedimentary rock.