The craters on Mercury are about __________ years old.
A) 4 thousand
B) 4 million
C) 4 billion
D) 4 trillion

Question

Quizplus · Accepted Answer

The craters on Mercury are estimated to be 4 billion years old, which indicates that the planet has remained relatively geologically inactive for this period. This is due to the lack of plate tectonics and a thick atmosphere to erode the surface. The age is determined by counting the number of craters per unit area, as older surfaces tend to have more craters.

The Craters on Mercury Are About __________ Years Old