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Q: For what kind of animal is communication essential? Read this paragraph and choose the correct option from the provided answers: Communication is any way that animals share information. Many animals live in social groups. For these animals, being able to communicate is essential. Communicating increases the ability of group members to cooperate and avoid conflict. Communication may help animals work together to find food and defend themselves from predators. It also helps them find mates and care for their offspring. In addition, communication helps adult animals teach the next generation learned behaviors. Therefore, communication generally improves the chances of animals surviving and reproducing. Choices: - anti-social animals - new born animals - migrating animals - social animals A:
(Answer)
social animals

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Q: What is the term for a solution that resists dramatic changes in ph? Read this paragraph and choose the correct option from the provided answers: As indicated in Section 12.4 "Strong and Weak Acids and Bases and Their Salts", weak acids are relatively common, even in the foods we eat. But we occasionally encounter a strong acid or base, such as stomach acid, which has a strongly acidic pH of 1.7. By definition, strong acids and bases can produce a relatively large amount of H+ or OHions and consequently have marked chemical activities. In addition, very small amounts of strong acids and bases can change the pH of a solution very quickly. If 1 mL of stomach acid [approximated as 0.1 M HCl(aq)] were added to the bloodstream and no correcting mechanism were present, the pH of the blood would decrease from about 7.4 to about 4.7a pH that is not conducive to continued living. Fortunately, the body has a mechanism for minimizing such dramatic pH changes. The mechanism involves a buffer, a solution that resists dramatic changes in pH. Buffers do so by being composed of certain pairs of solutes: either a weak acid plus a salt derived from that weak acid or a weak base plus a salt of that weak base. For example, a buffer can be composed of dissolved HC2H3O2 (a weak acid) and NaC2H3O2 (the salt derived from that weak acid). Another example of a buffer is a solution containing NH3 (a weak base) and NH4Cl (a salt derived from that weak base). Let us use an HC2H3O2/NaC2H3O2 buffer to demonstrate how buffers work. If a strong basea source of OH(aq) ionsis added to the buffer solution, those OH ions will react with the HC2H3O2 in an acid-base reaction:. Choices: - inert - neutral - stable - buffer A:
(Answer)
buffer

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Q: Why did people stop adding lead to gasoline? Read this paragraph and choose the correct option from the provided answers: Gasoline and oils are complex chemical mixtures designed to burn in a way that will efficiently produce energy while emitting a minimal amount of air pollution. The refining of gasoline has improved engine performance but is much more complicated than simply using the crude products extracted from oil wells, as was common in the late 1800s. Most gasoline contained lead at one time, because this additive helped the engine run more smoothly. However, this caused lead contamination in the environment, so new "unleaded" formulations were created that could be burned smoothly without the addition of poisonous heavy metals. Oils for lubrication have special additives that reduce engine wear. Some special fuel blends have also been created to generate more power in race car engines. Choices: - bad smell - to expensive - explosions - environmental pollution A:
(Answer)
environmental pollution