[Q]: I have a new situation: Robert, a baker, has just baked a large batch of cupcakes for his store. He won't be able to sell all of his cupcakes within the next week, so he has decided to store a portion of them in the freezer to preserve them for later. He is trying to decide if he should store the cupcakes at 0 F or at 10 F in the freezer. But I can use this background: Freezing is a common method of food preservation that slows both food decay and the growth of micro-organisms. Besides the effect of lower temperatures on reaction rates, freezing makes water less available for bacterial growth. What is an answer for this question: Which temperature will result in faster decay of the cupcakes?
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[A]: 10 F

[Q]: I have a new situation: Environmental scientists are trying to find a solution to reducing the harmful effects of chemicals on the environment. To that end, they developed a transgenic crop with the help of Bt toxin - they referred to it as case A. To test the effectiveness of this new crop they also studied Bt toxin spray - they referred to it as case B. They need to figure out which case is safer for the environment. But I can use this background: There is growing concern regarding the use of pesticides in agriculture. Therefore, many of the current commercial applications of modern biotechnology in agriculture are focused on reducing the dependence of farmers on these chemicals. For example, Bacillus thuringiensis (Bt) is a soil bacterium that produces a protein that can act as an insecticide, known as the Bt toxin . But it is a naturally occurring protein, not a foreign chemical. Could this protein be used in crops instead of pesticides? Traditionally, an insecticidal spray has been produced from these bacteria. As a spray, the Bt toxin is in an inactive state and requires digestion by an insect to become active and have any effect. Crop plants have now been engineered to contain and express the genes for the Bt toxin, which they produce in its active form. When an insect ingests the transgenic crop, it stops feeding and soon thereafter dies as a result of the Bt toxin binding to its gut wall. Bt corn is now commercially available in a number of countries to control corn borer (an insect like a moth or butterfly), which is otherwise controlled by insecticidal spraying. What is an answer for this question: In which case the Bt toxin does not need to be digested by the insects, case A or case B?
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[A]: case A

[Q]: I have a new situation: Gary researched two old human settlements. Village A was smaller, it existed about 12,000 years ago. He also studied village B, which existed about 6,000 years ago. The village was much bigger and better developed. But I can use this background: Human beings invented agriculture about 10,000 years ago. This provided a bigger, more dependable food supply. It also allowed people to settle down in villages and cities for the first time. Birth rates went up because there was more food and settled life had other advantages. Death rates also rose because of crowded living conditions and diseases that spread from domestic animals. Because the higher birth rates were matched by higher death rates, the human population continued to grow very slowly. What is an answer for this question: Which village had higher birth rates?
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[A]: village B

[Q]: I have a new situation: A doctor tested two people for HIV. Tom had the virus in his blood, while Nick didn't have HIV, he was healthy. Tom has apparently had the virus for 20 years. But I can use this background: As time passes, the number of HIV copies keeps increasing, while the number of helper T cells keeps decreasing. The graph in Figure below shows how the number of T cells typically declines over a period of many years following the initial HIV infection. As the number of T cells decreases, so does the ability of the immune system to defend the body. As a result, an HIV-infected person develops frequent infections. Medicines can slow down the virus but not get rid of it, so there is no cure at present for HIV infections or AIDS. There also is no vaccine to immunize people against HIV infection, but scientists are working to develop one. What is an answer for this question: Which person didn't have the number of HIV copies increasing as time passed?
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[A]:
Nick