The average monthly grocery bill for an individual is normally distributed with a mean of $85 and a standard deviation of $20

The average monthly grocery bill for an individual is normally distributed with a mean of $85 and a standard deviation of $20.

What is the probability that the grocery bill is more than $50?              

0.8413

0.96

0.1587

0.04

If you select 16 people, what is the probability that their mean grocery bill is more than $70?              

0.8413

0.0013

0.01587

0.999

If you select 4 individuals, what is the probability that their mean grocery bill is between $50 and $65?              

-3.5

0.023

1

0.977