Because it is called crude oil and believe it or not its hard to find. A lot of times the price will change because of where your located they may be having trouble finding and getting it. hope I helped ;)
What are high level factors that you would need to measure to inspect improvement in a functioning ecosystem? are drastic climate changes more crucial to an ecosystem than a change in magnitude?
In Manchester England in the 1840's there were factories that used coal which coated the trees. This allowed the darker moths to hide better against the trees than the lighter moths which were eaten by birds.
Phospholipid bilayer is the <span>component</span> of membrane contains a hydrophobic region and acts as the primary barrier to most foreign substances.
