What is the select that all apply?
Because the rock is laid down over time, the oldest rock (and fossils or whatever) will be in the lowest layer. As you go up, the age decreases - you are looking at younger rocks.
This doesn't tell you the *absolute* age of the rocks - you can't say from this evidence whether they are 100 million or 500 million years old. But you can see changes over history and you can get an ordering in time.
<span> they are: crossing over, independent assortment, and fertilization.
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The most obvious reason why scientists sill refer to viruses as being non-living would be the fact that D. Viruses are not composed of 1 or more cells. Since all living beings of life, from the early archae to the complex multi cellular mammalian organism everything is composed of these basic units of life.
