I dont know how to do it like how to graph the -x or the y

What value is a discontinuity of x squared plus 8 x plus 4, all over x squared minus x minus 6?

How do i take any fraction and make it into a decimal or percentage?

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?