It is how bright is is t the observer on earth...so wuld be c!!
this any help?
<span>Looking at the two species' DNA would be a good place to start. If there are a number of similarities in their genotypes, then there would be a good chance that the two would also share some type of a common ancestor. This would be evidence that there was some type of selection that took place that necessitated two different species that shared a number of traits and features.</span>
Answer: The troposphere.
It contains half of the earths atmosphere. Weather occurs in this layer.
