I really need help I don’t know how to do this pls

What is the binomial expansion of (2x-3)^5

Y=21.95x+10 y=22.45x solve by substitution

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?