Only Bella is correct, just took the test
<u>Weight : </u>
<em>⇒ x for 6 people</em>
<em>⇒ y for the 7th person</em>
<u>The correct answer is B).</u>
For normal distribution 95% lie in the range mean-2*standard deviation for lower bound and mean+2*standard deviation for upper bound.
Upper bound is 78+2*6=78+12=90
Lower bound is 78-2*6=78-12=66
B. 66 and 90