[Q]: John designed a hypothetical lever that would have ideal mechanical advantage. He labeled the lever as lever A. He then wanted to compare this lever with a real world lever, which he labeled as lever B. He intended to use these levers to increase force. Given the paragraph above, please answer correctly the following question: Would lever A have more friction or less friction than lever B? Hint: The Table above includes the ideal mechanical advantage of each class of lever. The mechanical advantage is the factor by which a machine changes the input force. The ideal mechanical advantage is the increase or decrease in force that would occur if there were no friction to overcome in the use of the machine. Because all machines must overcome some friction, the ideal mechanical advantage is always somewhat greater than the actual mechanical advantage of the machine as it is used in the real world.
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[A]: less friction

[Q]: Barb and Jill practiced small scale farming. Jill farmed the conventional way, while barb used the no-tillage method. Given the paragraph above, please answer correctly the following question: Which farmer didn't have soil that took longer to warm in spring? Hint: The benefits provided by no-tillage to predators may lead to larger predator populations, which is a good way to control pests (biological control), but also can facilitate predation of the crop itself. In corn crops, for instance, predation by caterpillars can be higher in no-till than in conventional tillage fields.In places with rigorous winter, untilled soil can take longer to warm and dry in spring, which may delay planting to less ideal dates. Another factor to be considered is that organic residue from the prior year's crops lying on the surface of untilled fields can provide a favorable environment to pathogens, helping to increase the risk of transmitting diseases to the future crop. And because no-till farming provides good environment for pathogens, insects and weeds, it can lead farmers to a more intensive use of chemicals for pest control. Other disadvantages of no-till include underground rot, low soil temperatures and high moisture.Based on the balance of these factors, and because each farm has different problems, agroecologists will not attest that only no-till or complete tillage is the right way of farming. Yet, these are not the only possible choices regarding soil preparation, since there are intermediate practices such as strip-till, mulch-till and ridge-till, all of them just as no-till categorized as conservation tillage. Agroecologists, then, will evaluate the need of different practices for the contexts in which each farm is inserted.
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[A]: Jill

[Q]: Two sisters Mary and Beth were into sciences. Beth studied physics, while Mary studied chemistry and especially alkanes. They were very devoted to studying. Given the paragraph above, please answer correctly the following question: Which sister studied less about the chemical formulas and properties of small alkanes? Hint: Saturated hydrocarbons are given the general name of alkanes . The name of specific alkanes always ends in ane . The first part of the name indicates how many carbon atoms each molecule of the alkane has. The smallest alkane is methane. It has just one carbon atom. The next largest is ethane with two carbon atoms. The chemical formulas and properties of methane, ethane, and other small alkanes are listed in the Table below . The boiling and melting points of alkanes are determined mainly by the number of carbon atoms they have. Alkanes with more carbon atoms generally boil and melt at higher temperatures.
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[A]: Beth

[Q]: John is studying a species in two similar countries, country A and country B. Country A has large population, but country B has small population of that species. John is pondering about how this species would fare in the future in these two countries. Given the paragraph above, please answer correctly the following question: In which country individuals of the species would have less food, country A or country B? Hint: In nature, when the population size is small, there is usually plenty of food and other resources for each individual. When there is plenty of food and other resources, organisms can easily reproduce, so the birth rate is high. As the population increases, the food supply, or the supply of another necessary resource, may decrease. When necessary resources, such as food, decrease, some individuals will die. Overall, the population cannot reproduce at the same rate, so the birth rates drop. This will cause the population growth rate to decrease.
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[A]:
country A