Ques:Q: Beryllium hydride consists of a central beryllium atom with two single bonds to what? Read this paragraph and choose the correct option from the provided answers: Beryllium hydride consists of a central beryllium atom with two single bonds to hydrogen atoms. Recall that it violates the octet rule. Choices: - nitrogen atoms - metabolic atoms - calcium atoms - hydrogen atoms A:

Ans:hydrogen atoms
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Ques:Q: What has the average global temperature done since the 1900s? Read this paragraph and choose the correct option from the provided answers: Average global temperature has risen since 1900. Choices: - stayed constant - changed randomly - decreased - risen A:

Ans:risen
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Ques:Q: What global cycle takes place on, above, and below earth's surface? Read this paragraph and choose the correct option from the provided answers: Water on Earth is billions of years old. However, individual water molecules keep moving through the water cycle. The water cycle is a global cycle. It takes place on, above, and below Earth's surface, as shown in Figure below . Choices: - aqua cycle - water flow - water wheel - water cycle A:

Ans:water cycle
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Ques:Q: In the past, what colliding with planet earth has caused many organisms to die off? Read this paragraph and choose the correct option from the provided answers: Near-Earth asteroids have orbits that cross Earth's orbit. This means that they can collide with Earth. There are over 4,500 known near-Earth asteroids. Small asteroids do sometimes collide with Earth. An asteroid about 510 m in diameter hits about once per year. Five hundred to a thousand of the known near-Earth asteroids are much bigger. They are over 1 kilometer in diameter. When large asteroids hit Earth in the past, many organisms died. At times, many species became extinct. Astronomers keep looking for near-Earth asteroids. They hope to predict a possible collision early so they can to try to stop it. Choices: - acid rain - meteorites - the Sun - asteroids A:

Ans:
asteroids
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