Answer: Photosphere
Explanation:
Photosphere, visible surface of the Sun, which is most of the Sun's light that reaches Earth directly.
Answer: A positive feedback loop occurs in nature when the product of a reaction leads to an increase in that reaction. If we look at a system in homeostasis, a positive feedback loop moves a system further away from the target of equilibrium.
Answer:
Explanation:
Geodesy, the science of measuring the Earth's shape and positions on it, allows the measurement of plate motion directly using GPS, the Global Positioning System. This network of satellites is more stable than the Earth's surface, so when a whole continent moves somewhere at a few centimeters per year, GPS can tell.
GPS uses a system of satellites to triangulate the position of a receiver anywhere on Earth. By using a network of receivers near plate boundaries, scientists can very accurately determine how the plates behave
In urban areas, there are more people, therefore not a lot of farmland. (that eliminates C) If city buildings don't allow flood waters to recede, that could be dangerous in many ways. (So A is still a reasonable answer) If most cities are built in flood zones, there should be some form of shelter if houses aren't safe. Pollutants and diseases being carried in water are already dangerous, but easier to spread with rapid flood waters that are sweeping everywhere. So your best answer would be either A or B.
Scientists believe convection currents are the force behind the plate tectonics theory.