Before a New Phone System Was Installed, the Amount a Company

Multiple Choice

Before a new phone system was installed, the amount a company spent on personal calls followed a normal distribution with an average of $500 per month and a standard deviation of $50 per
Month. Refer to such expenses as PCEʹs (personal call expenses) . Using the distribution above,
What is the probability that during a randomly selected month PCEʹs were between $375.00 and
$590.00?

A) .0421
B) .0001
C) .9999
D) .9579