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- A. occurs most infrequently
- B. is shifted sideways by strong winds
- C. is often hidden from our view
- D. is equipped with a good knowledge of various forms of lightning
- E. is estimated at 20 millions a year
- F. is positively charged
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In most cases of infra-cloud lightning, the ground's surface 1.
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One form of lightning that 1 is hall lightning.
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Cloud lightning looks like a ribbon when its lighting channel 1.
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Although not fully understanding processes of lightning, man 1.