Why is the soil on mountain slopes infertile and the soil in valleys fertile?

Variety of living organisms; includes genetic, species, and ecological types.

About how much of the cell mass is watet

How do you think earths interior affects what is happening on the surface? 2. how do fossils support the continental drift hypothesis? 3. how does sea- floor spreading support the hypothesis of continental drift? 4.what do scientists observe when they studied the magnetic fields of rocks on the sides of mid-ocean ridges? 5. what is a tectonic plate ? 6. explain mantle convection 7.how can movements of the continents affect earths climate? 8. what occurs during drifting?