Answer:
82 nails
Step-by-step explanation:
4.97 and 5.03 Â are both one standard deviation from the mean...
z scores   . 8413   and  .1587
.8413 - .1587 = .6826   or   68.26 %  of the nails are in this range
68.26 % Â * Â 120 = ~82 nails
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