6. How do scientists determine when an era begins and when it ends?

What is the approximate circumference of the circle shown below? 12.2 cm

In which area will soil formation be greatest? a a steep slope in a warm,b wet climate a flat area in a warm,c wet climate a north-facing area on a steep slope a flat area in a cold, d wet climate description

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