The mean amount of a purchase at the Smith Hardware store is $23.50 with standard deviation of $5.00. The amounts purchased follow normal distribution. 50 customers were sampled:
a.What is the likelihood the sample mean is at least $25.00?
b.What is the likelihood the sample mean will fall into the $22.50 to $25.00 range?
c.Within what limits will 90% of the sample means occur?