Answer: Typical examples of r-species are mice, rabbits, weeds and bacteria, which have a lot of offspring, but a short life expectancy. Examples of organisms undergoing K-selection are tortoises, elephants, people, and sequoia trees: their offspring are few but long-lived.
Explanation:
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.
<span>Ball and socket - Shoulder
Hinge joint - Elbow
Pivot Joint - Ulna/Radius
Plane joint - Wrist
Saddle joint - Thumb
Condyloid joint - Phalanges/Metacarpals</span>
1 fill the beaker with water
2 check the amount you have
3 drop the marble in and subtract the original amount with the one you have now
