Answer:
7.8 × 10-5 meters
Explanation:
the length of the a human hair= 8.4 x 10^-5
length of the vicuna hair:0.000006 = 0.6 x 10^-5
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difference between human hair and vicuna hair:
8.4 x 10^-5 - 0.6 x 10^-5 = 10^-5 ( 8.4 - 0.6)
= 10^-5 (7.8)
= 7.8 x 10 ^-5 meters