[Q]: I can use this background: A screw is a simple machine that consists of an inclined plane wrapped around a central cylinder. No doubt you are familiar with screws like the wood screw in the left-hand side of the Figure below . The cap of the bottle pictured on the right is another example of a screw. Screws move objects to a greater depth (or higher elevation) by increasing the force applied to the screw. Many screws are used to hold things together, such as two pieces of wood or a screw cap and bottle. When you use a screw, you apply force to turn the inclined plane. The screw, in turn, applies greater force to the object, such as the wood or bottle top. You can watch an animation of a turning screw at the following URL. Now, I have a new situation: At a new years party Mary brought an expensive bottle of champagne for the host. Just before midnight she goes and finds a corkscrew to open the bottle. She places the corkscrew on the cork and begins twisting it, making the corkscrew push itself into the cork so she can open the bottle easier. Answer this question please: Will the force applied to the corkscrew's inclined plane have increased or decreased after Mary finishes twisting it?
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[A]: increased

[Q]: I can use this background: Cholesterol can't dissolve in the blood. It has to be transported to and from the cells by carriers called lipoproteins. Low-density lipoprotein, or LDL, is known as "bad" cholesterol. High-density lipoprotein (HDL) is known as good cholesterol. When too much LDL cholesterol circulates in the blood, it can slowly build up in the inner walls of the arteries that feed the heart and brain. Together with other substances, it can form plaque, and lead to atherosclerosis. If a clot forms and blocks a narrowed artery, a heart attack or stroke can result. Cholesterol comes from the food you eat as well as being made by the body. To lower bad cholesterol, a diet low in saturated fat and dietary cholesterol should be followed. Regular aerobic exercise also lowers LDL cholesterol and increases HDL cholesterol. Now, I have a new situation: Mary and Ben went in for a blood test. Ben had high cholesterol, so the Doctor recommended him to lower it. Mary had normal cholesterol levels. Answer this question please: Which person was at higher risk of forming blood clots?
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[A]: Ben

[Q]: I can use this background: Old age begins in the mid-60s and lasts until the end of life. Most people over 65 have retired from work, freeing up their time for hobbies, grandchildren, and other interests. Stamina, strength, reflex time, and the senses all decline during old age, and the number of brain cells decreases as well. The immune system becomes less efficient, increasing the risk of serious illnesses such as cancer and pneumonia. Diseases such as Alzheimer's disease that cause loss of mental function also become more common. Now, I have a new situation: Two neighboring towns had different demographics. Hill town had younger inhabitants, most of them in their 30's and 40's. Lake town was inhabited by elderly people, most of them above 65 years of age. Answer this question please: Which town had more people that freed up time for their grandchildren?
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[A]: Lake

[Q]: I can use this 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/ . Now, I have a new situation: Sam and Ned went on vacation, The 2 friends partied nights and spent their days on the beach. Sam started getting flu like symptoms, so he went to the doctor's office where he found out that he was infected with HIV. Ned got scared when he heard what happened, but fortunately he was OK. Answer this question please: Which friend contracted a virus that originated in sub-Saharan Africa during the 20th century?
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[A]:
Sam