Answer:
The correct answer is A. a rotating cloud of dust and gas.
Explanation:
Nebulae are regions of the interstellar medium (clouds) made up of gases (mainly hydrogen and helium) and dust. In other words, nebulae are concentrations of gas in which we find hydrogen, helium and stardust in greater quantities. They are structures that are actually very important for the universe, this because inside it is the place where stars are born, which arise due to the condensation and aggregation of matter. The nebular theory states that the Solar System reached the form current from a solar nebula (a gas cloud), more than 4.5 billion years ago. The large cloud of molecular gas was affected by a certain phenomenon that would have taken place in the vicinity. Like the explosion of a supernova or the passage of a star that would produce a strong gravitational impact. The result of this event made the matter agglomerate in different places. The high concentration of matter caused the nebula to collapse. Becoming a protostar, (bodies whose characteristic is to be surrounded by clouds and contain preplanetary matter inside), that is, gaseous matter in the outermost part and solid inward. At the core of this structure, the temperature is so dominant that nuclear reactions take place to compensate for the gravitational force. This leads to a hydrostatic equilibrium and the formation of a fundamental star: the Sun. The rest of the mass flattened, forming a protoplanetary disk where the protoplanets were being formed, which would evolve to become the current planets, their satellites and the others bodies of the solar system.
Rickets is the disease in children in which an inefficient mineralization of the bone forming tissue causes deformities. This condition results in weak or soft bones in children, normally due to an extreme and prolonged deficiency of vitamin D. Vitamin D promotes the absorption of calcium and phosphorus from the gastrointestinal tract. The symptoms include bowed legs, stunted growth, bone pain, large forehead, and trouble sleeping among others.
Exploring the city with trolley cars and many hills. This city is San Francisco, CA.
Trolley cars or cable cars were introduced in 1873 to enable locals to contend with many hills the city is built on. Now, tourists ride the cable cars and will be given a tour of the city.
Answer:
eating cereal with no cholesterol would decrease the amount you normally eat which can led to preventing or reversing harding of the arteries, maintain a healthy weight, and can help adults with type 2 diabetes. it is important though that you are still eating cholesterol, don’t cut it out or it can cause serious heath problems