If you're referring to streams/rivers of water that run independently of another source in the ocean these are referred to as "currents" and can be very powerful depending on their location.
Answer:
b. flat rotation curves in spiral galaxies
Explanation:
Dark matter accounts for majority of the matter in the universe (about 85%). It is considered to be composed of subatomic particles which are yet to be discovered. Dark matter cannot be observed because it does not emit light that can be detected. Only its gravitational effect is visible.
Astronomers when calculated the mass of the visible matter and tried to account for the observed speed of stars in the galaxy, there was a mismatch. To understand what caused this mismatch, astronomers gave name to the invisible matter as the Dark Matter.
The expected velocity of stars should decrease away from the near the center of the galaxy but a constant velocity of stars was observed that is a relatively flat rotation curve was obtained.
Thus, flat rotation curves in spiral galaxies in an evidence of Dark Matter.
Answer:
(a) Lower densities and higher thermal gradient
Explanation:
Over pressured zones during penetrating are those zones where development liquid weight (higher than expected) surpasses the mud weight. These are liable for victories.
- The pore liquid substance in shales of the over constrained zone is higher than the ordinary compelled shales. That implies, the porosity of shales in over pressured zone is higher as well thus the thickness of the over forced zones are lower than the ordinary influenced shales.
- Because of the nearness of more liquids in the pores of an over constrained shale, the warmth produced because of penetrating behaviors gradually in over influenced shale than a shale in typical weight zones. Accordingly, warm inclination will be higher in over forced shales.
Economic opportunities seems to be the driving factor for migration nowadays. An example of a group of migrants migrating from areas with a lack of economic opportunities to areas with more economic opportunities are Mexican immigrants seeking job opportunities.
The spinning of Earth on its axis is Earth's rotation.
