Problem: I read this background article the other day: In addition to insects, weeds have also been a menace to farmers - just ask anyone with a garden how much they hate weeds. They can quickly compete for water and nutrients needed by other plants. Sure, farmers can use herbicides to kill weeds, but do these chemicals also harm the crops? Can biotechnology help with this issue? Some crops have also been genetically engineered to acquire tolerance to the herbicides - allowing the crops to grow, but killing the weeds. But the lack of cost effective herbicides with a broad range of activity - that do not harm crops - is a problem in weed management. Multiple applications of numerous herbicides are routinely needed to control the wide range of weeds that are harmful to crops. And at times these herbicides are being used as a preventive measure that is, spraying to prevent weeds from developing rather than spraying after weeds form. So these chemicals are being added to crops. This practice is followed by mechanical and/or hand weeding to control weeds that are not controlled by the chemicals. Crops that are tolerant of herbicides would obviously be a tremendous benefit to farmers ( Figure above ). The introduction of herbicide tolerant crops has the potential to reduce the number of chemicals needed during a growing season, thereby increasing crop yield due to improved weed management and decreased harm to the crops. I am facing a new situation today: Vince had a small rural farm. He needed to increase production and efficiency, so he started using herbicides. Danny was one of his farmer friends, he had a small acreage farm and he practiced permaculture, so no pesticides. Using the knowledge I acquired from the background article, how should I answer correctly the following question regarding my new situation: Which farmer increased the crop yield?

A: Vince
Problem: Given the question: I read this background article the other day: The Hawaiian Islands ( Figure above ) are in the central Pacific Ocean. The islands are volcanoes that increase in age from southeast to northwest. The youngest island is the Big Island of Hawaii at the southeast end of the chain. The volcanoes get older through Maui, Kahoolawe, Lanai, Molokai, Oahu, Kauai, and Niihau Islands through the northwest. The Kilauea volcano on Hawaii has been erupting almost continuously since 1983. There are also eruptions at an underwater volcano called Loih I am facing a new situation today: Pete lived in Alaska, but visited his friend Julia from Hawaii very often. They had many mutual interests, including geology and earthquakes. Using the knowledge I acquired from the background article, how should I answer correctly the following question regarding my new situation: Which person lived farther from Oahu island?
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The answer is:
Pete
input question: I read this background article the other day: Another thing we can see in this animation is that particles are constantly colliding with one another. One assumption that we make when talking about collisions between gas particles is that they are completely elastic collisions. In an elastic collision , momentum is conserved, which means that none of the kinetic energy of the colliding particles is lost in some other form (such as the emission of light). This makes sense, because if energy were lost in collisions, the speeds of the particles would gradually decrease over time, and eventually everything would condense down into a solid form. I am facing a new situation today: Dan is in his physics lab. He is experimenting with colliding particles. He has two samples of particles, sample A and sample B. Sample A contains gas particles, but sample B does not contain gas particles. Using the knowledge I acquired from the background article, how should I answer correctly the following question regarding my new situation: Would momenturm be conserved or not conserved in sample B????
output answer: not conserved
I read this background article the other day: If a solution has a higher concentration of hydronium ions than pure water, it has a pH lower than 7. A solution with a pH lower than 7 is called an acid . As the hydronium ion concentration increases, the pH value decreases. Therefore, the more acidic a solution is, the lower its pH value is. Did you ever taste vinegar? Like other acids, it tastes sour. Stronger acids can be harmful to organisms. For example, stomach acid would eat through the stomach if it were not lined with a layer of mucus. Strong acids can also damage materials, even hard materials such as glass. I am facing a new situation today: Mike is studying chemistry for his exam. Today, he is studying the properties of acids. He picks up an acid solution that he labels as solution A. To compare it with another solution he chooses a solution that is not an acid. He labels it as solution B. Using the knowledge I acquired from the background article, how should I answer correctly the following question regarding my new situation: Would solution A have higher or lower pH value than solution B?
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Answer: lower
Q: I read this background article the other day: 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. I am facing a new situation today: Barb and Jill practiced small scale farming. Jill farmed the conventional way, while barb used the no-tillage method. Using the knowledge I acquired from the background article, how should I answer correctly the following question regarding my new situation: Which farmer had soil that took longer to warm in spring?
A: Barb
[Q]: I read this background article the other day: If a solution has a higher concentration of hydronium ions than pure water, it has a pH lower than 7. A solution with a pH lower than 7 is called an acid . As the hydronium ion concentration increases, the pH value decreases. Therefore, the more acidic a solution is, the lower its pH value is. Did you ever taste vinegar? Like other acids, it tastes sour. Stronger acids can be harmful to organisms. For example, stomach acid would eat through the stomach if it were not lined with a layer of mucus. Strong acids can also damage materials, even hard materials such as glass. I am facing a new situation today: Alexiev and Sabrina were enthusiastic chemistry students completing the first experiment of their new course. They both started the experiment with pure water, and had to perform different experimental protocols to make changes to the water. At the end of the experiment, both of them measured the concentration of hydronium ions present in their reaction mixtures. Alexiev had a high concentration of hydronium ions present, while Sabrina had a low concentration present in her mixture. Using the knowledge I acquired from the background article, how should I answer correctly the following question regarding my new situation: Which person's mixture, Alexiev's or Sabrina's, would taste more sour at the end?
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[A]:
Alexiev's