The correct answer is - cyanobacteria.
The atmospheric oxygen came from the cyanobacteria. These were one of the earliest living organisms on Earth. The cyanobacteria was using photosynthesis in order to create its own food. The photosynthesis process requires sunlight, carbon dioxide, water, and oxygen. The oxygen is mostly released as a waste product from the process of photosynthesis, thus the cyanobacteria were literally releasing oxygen that was ending up into the atmosphere. As more and more cyanobacteria there were across the planet, more and more oxygen they were releasing into the atmosphere, slowly changing the composition of the atmosphere, and setting the basis of it as we know it now.
The convection currents are the ones that create the force that breaks up and moves the crustal plates on the surface of the planet. By moving the crustal plates, the convection currents contribute to the formation of different types of plate boundaries, including the divergent plate boundaries.
The divergent plate boundaries are the boundaries where two plates are moving away from one another because the convection currents are dictating that kind of movement from bellow them. As they move away from each other, they leave a gap between them, and the convection currents push up a lot of magma towards the surface. The magma cools of very quickly in the water, thus forming rocks constantly, rocks that little by little start to make a big mas, that eventually turns into an underwater mountain, or rather a mid-ocean ridge.
Answer:
m greater than 1 ok class 9 ok I am
8 pounds hope this helps!!!
A globular cluster is a collection of stars in the form of a sphere that orbits a galactic core. Global clusters are generally tightly bound by gravity, making the stellar density higher toward the center, and giving them their spherical shapes. Globular clusters are usually found in the halo of a galaxy.
The fact that the gravitational pull of a globular cluster is rather weak means that a single supernova explosion can blow the interstellar gas out of a globular cluster. This would mean that the gas left is not dense enough to form new stars. After the first generation, globular clusters cease to form new stars because they lack material due to their deficiency in heavy elements.
