Clea attends music lessons every 2 weeks, dance class every 3 weeks, and has a dental appointment every 6 weeks. if she attends all three this week, when will she attend all three again

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?