Problem: Given the background: 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/ . and the situation: Monica and Jill are two friends. They study and party together most of the time. One day Monica shared a needle with a drug addict at a party. She later found out that she'd been infected with HIV. Jill was scared and helped her as much as she could. Answer the following question: Which friend doesn't have the virus that causes Acquired Immunodeficiency Syndrome?

A: Jill

Problem: Given the background: Current Situation : Currently the heating effect of extra greenhouse gases (since the start of the industrial revolution) is equal to about . Thus the recent period has recorded parallel increases in concentration of carbon dioxide and average global temperature. As more greenhouse gases are put into the atmosphere the temperature will increase further. There are certain effects of a warmer Earth (discussed more in optional section), which could accelerate the process, even if no more greenhouse gases are put into the atmosphere (an unlikely prospect for the foreseeable future). and the situation: There is a local election in Troy's city and he is researching the two candidates running for mayor. Troy is a strong environmentalist who believes, above all else, that taking care of the Earth is the number one priority in anything. In his research he decides to read the environmental proposals of each candidate. Mark Hampton, one candidate, has a proposal that he says will strongly boost the city's economy by opening more industrial factories, but these will increase the carbon dioxide put into the atmosphere. Jeffrey Lindell, the other candidate, says that he wants to begin implementing solar panel farms to generate electricity to cut down on the carbon emissions the city produces. Answer the following question: Which candidate's proposal will cause an increase in global temperature?

A: Mark Hampton

Problem: Given the background: The mechanical advantage of a machine is the factor by which it changes the force applied to the machine. Many machines increase the force applied to them, and this is how they make work easier. Compound machines tend to have a greater mechanical advantage than simple machines. That's because the mechanical advantage of a compound machine equals the product of the mechanical advantages of all its component simple machines. The greater the number of simple machines it contains, the greater its mechanical advantage tends to be. and the situation: David was studying the processes involved in a machine. He collected a simple machine. He tagged it as case A. To compare it with compound machines, he collected two compound machines, case B and case C. Case B is a compound machine with few simple machines. And, case C is a compound machine with many simple machines. Answer the following question: Would case B have greater or smaller mechanical advantage than case A?

A: greater

Problem: Given the background: Some individuals have a specific mutation in the primary sequence of their hemoglobin molecules that causes them to aggregate, resulting in a deformation of their red blood cells. This abnormality is genetic in nature. A person may inherit the gene from one parent and have sickle cell trait (only some of the hemoglobin is hemoglobin S), which is usually not life-threatening. Inheriting the gene from both parents will result in sickle cell disease, which is a very serious condition. and the situation: Doctors studied two groups of patients. Group W which had people with sickle cell disease, and group A which had normal people in it. Answer the following question: Which group had fewer individuals with genetic abnormalities?

A:
group A