Ques:Q: Pollutants in surface water can filter into the ground and enter a what? Read this paragraph and choose the correct option from the provided answers: Pollutants in surface water can filter into the ground and enter a groundwater aquifer. Irrigation water can bring pesticides and other chemicals. Water can seep through landfills. Tanks of gasoline stored underground can leak. Choices: - hydro plant - turbine - combustion aquifer - groundwater aquifer A:

Ans:groundwater aquifer
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Ques:Q: Where are protons and neutrons located? Read this paragraph and choose the correct option from the provided answers: Protons and neutrons are located in a central nucleus, while electrons orbit about the nucleus. Choices: - outside the nucleus - secondary nucleus - orbitals - central nucleus A:

Ans:central nucleus
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Ques:Q: Why will water balloons launched into the air eventually burst? Read this paragraph and choose the correct option from the provided answers: Each day, hundreds of weather balloons are launched. Made of a synthetic rubber and carrying a box of instruments, the helium-filled balloon rises up into the sky. As it gains altitude, the atmospheric pressure becomes less and the balloon expands. At some point the balloon bursts due to the expansion, the instruments drop (aided by a parachute) to be retrieved and studied for information about the weather. Choices: - heat - momentum - friction - expansion A:

Ans:expansion
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Ques:Q: The earth's magnetic poles have done what repeatedly in the past? Read this paragraph and choose the correct option from the provided answers: Earth's magnetic poles have switched places repeatedly in the past. As you can see in the Figure below , each time the switch occurred, Earth's magnetic field was reversed. The magnetic field is the region around a magnet over which it exerts magnetic force. We think of today's magnetic field direction as "normal," but that's only because it's what we're used to. You can watch a simulation of a magnetic field reversal at this URL: http://www. pbs. org/wgbh/nova/earth/when-our-magnetic-field-flips. html. Choices: - rotated - stayed the same - demagnetized - switched places A:

Ans:
switched places
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