Which of the following tools is most useful for tightening a small mechanical fastener?
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OPTIONS:
- chisel
- pliers
- sander
- saw

pliers

The Moon is visible to observers on Earth because of
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OPTIONS:
- reflected sunlight
- absorbed light from Earth's atmosphere
- gases in the Moon's interior
- volcanic eruptions on the Moon's surface

reflected sunlight

Which of the following is the best estimate of the number of stars in a typical galaxy?
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OPTIONS:
- tens
- hundreds
- thousands
- billions
billions