An author of childrens online educational games wants to use statistics to decide on the price that each game should sell for. After surveying similar games sold by competitors, the author finds that the price of this type of games is normally distributed with a mean price of 18$ and a standard deviation 4.25$

a) if the author of the games wants to set the price such as 90% of the competitors prices exceed authors price, what price should she set?

b)If the author wants to price her games, so as to be in the middle 80% range of her competitors prices, what should the maximum game price be and what should the minimum price be?