Please help! This is a Algebra 1 question Xavier is paying his friend to make pizzas for his fundraiser for school. It ended up costing $1200 after $40 delivery charge and $10 worth of ingredients per pizza. How many pizzas did he have made?

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?