It is estimated that 20 patrons will attend an event for every $100 spent in advertising. if tickets cost $40, how much can a promoter expect to increase sales if he spends $10,000 in advertising?

1. according to the internal revenue service, the mean tax refund for the year 2007 was $2,708. assume the standard deviation is $650 and that the amounts refunded follow a normal probability distribution. a. what percent of the refunds are more than $3,000? b. what percent of the refunds are more than $3,000 but less than $4,000? c. what percent of the refunds are less than $2,000?