[Q]: 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: Jeremiah and Alexander are students in a work shop class at their local community college. For their final project, they have to construct a compound machine to carry bricks across a room. Jeremiah's compound machine consists of many simple machines. Alexander's compound machine only consists of a few simple machines. Answer the following question: Which person's compound machine will have a larger mechanical advantage?
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[A]: Jeremiah's

input: Please answer the following: 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: Two colleagues gave blood for an emergency. Ned got infected with HIV because they re-used a needle. His friend Nate was not infected. Answer the following question: Which colleague didn't have a virus that is transmitted by contact with infected breast milk?
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output: Nate

Please answer this: Given the background: Electric potential energy comes from the position of a charged particle in an electric field. For example, when two negative charges are close together, they have potential energy because they repel each other and have the potential to push apart. If the charges actually move apart, their potential energy decreases. Electric charges always move spontaneously from a position where they have higher potential energy to a position where they have lower potential energy. This is like water falling over a dam from an area of higher to lower potential energy due to gravity. and the situation: David is interested in how electricity works. One day he had two electric charges to investigate, charge A and charge B - both of the charges were negative. He also had two electric fields, field C and field D. He noticed that electric charges were moving from field C to field D. Answer the following question: If charge A and charge B are closer, would their potential energy increase or decrease?
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Answer: increase

Problem: Given the background: During sexual reproduction, mating with a close relative (inbreeding) often leads to inbreeding depression. Inbreeding depression is considered to be largely due to expression of deleterious recessive mutations. The effects of inbreeding have been studied in many vertebrate species. and the situation: Keith is a zoologist. He studies large predators. Last year, he was studying different species of lions. First, he visited the Gir forest in India. There he found the Asiatic Lions. Unfortunately, only few Asiatic Lions are left in the wild, and they have to mate with their close relatives. He then visited the Serengeti reserve in Tanzania. There he found that the African Lions were not forced to mate with close relatives due to their large number. Answer the following question: Which lion species would be more prone to inbreeding, Asiatic or African?

A: Asiatic

Problem: Given the question: Given the background: Some materials have negative heats of solution; the dissolution of one of these solutes in water is an exothermic process. Heat is released, causing a net increase in the temperature of the solution. Conversely, other substances have positive heats of solution. For example, the dissolution of potassium nitrate in water is an endothermic process. The resulting absorption of energy causes the solution to become colder. Calculations involving heats of solutions follow the same basic approach that we have used with other enthalpy problems. and the situation: A scientist is in the lab testing mixing water with different chemicals. While working with chemical A he notes that the water becomes colder after combining them. With chemical B the water becomes much warmer. Answer the following question: Which of the two chemicals causes an endothermic process, chemical A or chemical B?
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The answer is:
chemical B

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: Two colleagues gave blood for an emergency. Ned got infected with HIV because they re-used a needle. His friend Nate was not infected. Answer the following question: Which colleague had a virus that causes Acquired Immunodeficiency Syndrome ( AIDS )?

A:
Ned