Ques:Answer the following question given this paragraph: Humans have sent spacecraft up to study our star. The SOHO spacecraft has been in operation since 1996. The craft orbits the Sun in step with Earth but closer to it. SOHO has sent back amazing images. Onboard instruments have also sent back mountains of data. The data is mostly about the Sun's outer layers. Q: What year did the soho spacecraft first started to operate? Choices: - 2012 - 2006 - 1987 - 1996 A:

Ans:1996
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Ques:Answer the following question given this paragraph: Indeed, scientists discovered something astonishing. Many times in Earth's history, the magnetic poles have switched positions. North becomes south and south becomes north! When the north and south poles are aligned as they are now, geologists say it is normal polarity. When they are in the opposite position, they say that it is reversed polarity. Q: What feature of the land do contour lines show? Choices: - trails - flat surfaces - bodies of water - three-dimensional shape A:

Ans:three-dimensional shape
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Ques:Answer the following question given this paragraph: Peroxisomes Like lysosomes, a peroxisome is a membrane-bound cellular organelle that contains mostly enzymes (Figure 3.17). Peroxisomes perform a couple of different functions, including lipid metabolism and chemical detoxification. In contrast to the digestive enzymes found in lysosomes, the enzymes within peroxisomes serve to transfer hydrogen atoms from various molecules to oxygen, producing hydrogen peroxide (H2O2). In this way, peroxisomes neutralize poisons such as alcohol. In order to appreciate the importance of peroxisomes, it is necessary to understand the concept of reactive oxygen species. Q: Peroxisomes perform a couple of different functions, including lipid metabolism and chemical detoxification. in contrast to the digestive enzymes found in lysosomes, the enzymes within peroxisomes serve to transfer hydrogen atoms from various molecules to oxygen, producing what? Choices: - calcium - water - hydrogen - hydrogen peroxide A:

Ans:hydrogen peroxide
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Ques:Answer the following question given this paragraph: Catalysts interact with reactants so the reaction can occur by an alternate pathway that has a lower activation energy. Activation energy is the energy needed to start a reaction. When activation energy is lower, more reactant particles have enough energy to react so the reaction goes faster. Many catalysts work like the one in the Figure below . (You can see an animated version at the following URL. ) The catalyst brings the reactants together by temporarily bonding with them. This makes it easier and quicker for the reactants to react together. Notice how the catalyst is released by the product molecule at the end of the reaction. Q: What is the energy needed to start a reaction between catalysts and reactants called? Choices: - reaction energy - decomposition energy - conductivity energy - activation energy A:

Ans:
activation energy
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