According to the Show Box Office at the Smythe Production Company, the mean cost to run a performance is $3000. Assume that the standard deviation is $410 and that the performance cost follows a normal probability distribution.
a. What percentage of the performances cost more than $3100 to run?
b. What percentage of the performances cost more than $3100 but less than $3500 to run?
c. What percentage of the performances cost more than $2250 but less than $3500 to run?