Low beam headlamps are only effective for speeds up to mph.

_20 to 25_ mph

Explanation:

Low beam headlamps are only effective for speeds up to __20 to 25_ mph.At higher speeds Low beam headlamp prove to be ineffective.Low beam headlamps are more effective in Fog, mist or snow. High beam headlamp directly shine in fog or precipitation, reflecting the light back into you.  

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yup its correct its: c) b b

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