Answer:
Geographic isolation
Explanation:
Geographic isolation is a term that refers to a population of animals,plants and other organisms that are separated from exchanging genetic materials with other organisms of the same species. This usually occur as a result of accident or coincidence.
Liocleonus clathratus usually referred to as L. Clathratus is a species of cylindrical weevils that belongs to the curculionidae family . It can reach a length of 1cm.The body is elongated and the basic coloration is white, with
longitudinal black markings on the pronotum and elytrae.
When a Plateau is been divided into a valley as a result of natural factors such as earthquake or erossion, plants and organisms are been isolated or separated from their mass habitation. This right here is coincidental and a natural accident .
The ability to reproduce species of their kind will be limited since they are not able to exchange genetic materials with other organisms of same species as each one will be displaced into different location.
Answer: True
Explanation: Jetties are structures constructed perpendicular to shore. They form a 90 degree angle to the shore and cause sediment to accumulate on the updrift side. This is the side that provides sediments.
Jetties are made of heaps of stones or concrete deposited at coastal inlets. They change the longshore current, and due to this, create updrift beaches.
Shoreline Structures such as jetties, and seawells help protect the shoreline from erosion and lessen the effect of currents and waves on the shoreline.
Answer: The release of methane from thawed permafrost
Explanation:
With increasing global warming, permafrost in the arctic is melting. The carbon and methyl clathrates present in permafrost escape into the atmosphere to form carbon dioxide and methane, both greenhouse gases.
In the Arctic, molecules of methane are trapped in ice crystals as methyl clathrates. When the temperature increases, these crystals release methyl clathrates which become methane when in contact with the atmosphere.
The cause of the increasing atmospheric 
is due to the the thawing of dead organisms present in the permafrost. As the permafrost melts, these organisms decay and release into the atmosphere.
I think it's A but here's an explanation anyway: as you heat the crude oil, the different hydrocarbons, having different boiling points, boil and evaporate up the column. Those with lower boiling points, shorter in chain length, will condense nearer the top of the fractional distillation column. Those that are more viscous, larger in chain size, will have high boiling points, so will evaporate last and condense lower down in the column. Therefore, you achieve all the different oils / materials (oil, petrol, gasoline, tar etc etc). I hope this helps. If not, then a good website to use is 'BBC bitesize, fractional distillation'.
