user: Q: I read this background article the other day: The general trend in electronegativity is that the value increases from left to right across a row in the periodic table and decreases down a column. The most electronegative element is fluorine, which has a value of 4.0. As discussed in the lesson "Trends in the Periodic Table," electronegativity increases across a row as the number of protons in the nucleus increases and therefore has a stronger pull. Electronegativity decreases down a column due to an increased effect of electron shielding in larger atoms.  I am facing a new situation today: Mike has to learn more about the periodic table for his chemistry exam. To make things easier for him he chose two elements from the table, element A and element B. Element A has higher electronegativity and element B has lower eletronegativity. David found it easier to learn about elements by comparing their properties.  Using the knowledge I acquired from the background article, how should I answer correctly the following question regarding my new situation: Where element A most likely be across the row, left or right?
A: right

Q: I read this background article the other day: The Human Immunodeficiency Virus ( HIV ) is the virus that causes Acquired Immunodeficiency Syndrome ( AIDS ). Most researchers believe that the HIV originated in sub-Saharan Africa during the 20th century. HIV is transmitted by sexual contact and by contact with infected bodily fluids, such as blood, semen, breast milk, and vaginal secretions. It is also passed from mother to fetus. HIV is now a pandemic , with an estimated (as of 2008) 38.6 million people now living with the disease worldwide. It is estimated that AIDS has killed more than 25 million people since it was first recognized in 1981. For further information about HIV/AIDS, see the CDC (Centers for Disease Control and Prevention) web site at http://www.cdc.gov/hiv/resources/factsheets/ .  I am facing a new situation today: Two colleagues gave blood for an emergency. Ned got infected with HIV because they re-used a needle. His friend Nate was not infected.  Using the knowledge I acquired from the background article, how should I answer correctly the following question regarding my new situation: Which colleague didn't have a virus that causes Acquired Immunodeficiency Syndrome ( AIDS )?
A: Nate

Q: I read this background article the other day: Currently, millions of individuals with high cholesterol take a similar type of drug, known as a statin. The drug, an inhibitor of HMG-CoA reductase (3-hydroxy-3-methyl-glutaryl-CoA reductase), the rate limiting enzyme in cholesterol biosynthesis, decreases blood levels of cholesterol by induce the expression of low density lipoprotein (LDL) receptors in the liver. The increased levels of the LDL-receptors stimulate the catabolism of plasma LDL, removing cholesterol from plasma, which is an important determinant of atherosclerosis. You may know of people who take a statin to help with their cholesterol levels. However, these drugs probably work slightly differently in many of those people. In some, it lowers their cholesterol significantly; in others it may lower it only moderately; and in some, it may have no significant effect at all. (Luckily for those individuals, there are multiple versions of the statins, so different drugs can be tested to find the proper combination for that individual.) Why the difference? Because of the genetic background of all people; the different single nucleotide polymorphisms that make us all different. Pharmacogenomics, a combination of pharmacology and genomics (the study of the genome) that refers to the study of the relationship between pharmaceuticals and genetics, may explain and simplify this problem.  I am facing a new situation today: Uncle Tom and uncle Sam both have high cholesterol. Uncle Tom is on statin drugs and uncle Sam is not.  Using the knowledge I acquired from the background article, how should I answer correctly the following question regarding my new situation: Which uncle takes an inhibitor of the rate limiting enzyme in cholesterol biosynthesis?
A: Tom

Q: I read this background article the other day: Besides anthropogenic productivity of the land, the biodiversity of degraded land also declines, as previously mentioned.[12] With less biodiversity, this ecosystem is less adaptable to when disasters strike it[11][8] It has a smaller available food supply, in terms of plants, for animals, who then may die out or more likely may relocate. Proof of this decline is that presently 15-20% of Tibetan Plateau species are now considered endangered; and now because of this animal and plant absence, the soil quality of these degraded lands is very poor.[1] It does not hold the necessary nutrients, such as water, nitrogen, and carbon, essential to either supporting life or inviting life back to that land.[6] As a result of such carbon and nitrogen loss in the Tibetan Plateau, $8,033/ha and $13,315/ha were respectively lost in economic terms. Soils are further weakened by dust storms whose frequency increases because of degradation.[11][4] Erosion of soil becomes a bigger problem, since no longer are there as many plants to anchor in the soil. In the northern Chinese province alone, 400 million are affected every year with an associated 54 billion yuan of annual economic loss due to grassland degradation.  I am facing a new situation today: Both Nicaragua and Costa Rica had large tract of pristine forests. They had one of the largest concentration of tropical species. In the 1980s Nicaragua started clearing up some of these forests. Instead, they have now vast tract of sugarcane production in that land. One can still visit Costa Rica where they kept those pristine forests intact.  Using the knowledge I acquired from the background article, how should I answer correctly the following question regarding my new situation: Will Nicaragua have smaller or larger plant food supply for its indigenous animals?
A:

assistant: smaller