By the mid 2030's. You can find it on their website.
The correct answer is - d. colder and denser.
The main differences between the surface currents and deeper currents are the temperature and density, and that actually decides their position in the water, on the surface, or deeper.
The surface currents are warmer, and because they are warmer the molecules are much more loose, so the density is lower, which in return makes it easier, thus it is in the surface.
The deeper currents are colder, and because they are colder the molecules are much closer and more concentrated, so the density is higher, which means that they are heavier, thus fall deeper below the easier currents.
Answer:
The Hadean eon represents the time interval between 4.6 billion to 4 billion years back. It is marked by the initial formation of the earth , right from the time of gathering and accumulation of interstellar dust particles and gases, and there was frequent collision between the planetesimals of relatively larger in size. The core and the crust formed and started to become stable and also gradually led to the formation and expansion of the ocean and the earth's atmosphere.
This is how the earth gradually started to form and develop and took the shape during the time interval between 4.6 billion to 4.2 billion years old, and where the oldest rocks found on earth is dated from about 4.2 billion years in the past.
Tornado activity is monitored mostly by the
<span>Storm Prediction Center and the National Climatic Data Center.
Hope that helps!</span>