Roberto bought 3 packs of pens for $3.59 per item.. If the sales tax rate is 8%, find the total amount of tax he paid for all those pens he purchased.

Determine the mean and variance of the random variable with the following probability mass function. f(x)=( 729divided by 91) (1 divided by 9) superscript x baseline comma x equals 1,2,3 round your answers to three decimal places (e.g. 98.765).

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?

In the diagram, bc¯¯¯¯¯∥de¯¯¯¯¯ . what is ce ? enter your answer in the box.