Answer:
Explanation:
Helium is the second most abundant element in the universe, but here on earth, it's rather rare. Most people guess that we extract helium from the air, but actually we dig it out of the ground. Helium can be found in certain parts of the world, notably in Texas, as a minor component in some sources of natural gas.
Helium is generated underground by the radioactive decay of heavy elements such as uranium and thorium. Part of the radiation from these elements consists of alpha particles, which form the nuclei of helium atoms. ... Helium can also be produced by liquefying air and separating the component gases
When the gas contains more than about 0.4% helium by volume, a cryogenic distillation method is often used in order to recover the helium content. Once the helium has been separated from the natural gas, it undergoes further refining to bring it to 99.99+% purity for commercial use.
Answer:
True.
Explanation:
Polygeny occurs in organisms with complex genomes, when several pairs of genes interact to determine a trait, each with an additive effect on the other. Thanks to this type of interaction there is a very wide variety of phenotypes and genotypes for some characteristics. The interaction of these phenotypes with the environment further increases this variation, such as skin color and height, etc. In other words, polygeny is the state of a particular trait determined by the relationship or action of various genes.
Answer:
d
Explanation:
The answer would be d because limitation of models is basically about non realistic part of models that separate them from real life which is what d is saying.
<span>A callus is important to a healing fracture because it encloses the fracture site, creating a temporary bridge between the bones. This is important to facilitate healing and repair for the bone. It allows the bones to slowly grow back together, and it is eventually replaced with bone tissue and reabsorbed into the body over time.</span>
