Steps please and please explain NORMSINV is and how to find it. I think that's where I went wrong.

Problem 20-14 (Algo) Charlie's Pizza orders all of its pepperoni, olives, anchovies, and mozzarella cheese to be shipped directly from Italy. An American distributor stops by every five weeks to take orders. Because the orders are shipped directly from Italy, they take four weeks to arrive. Charlie's Pizza uses an average of 260 pounds of pepperoni each week, with a standard deviation of 38 pounds. Charlie's prides itself on offering only the best-quality ingredients and a high level of service, so it wants to ensure a 99 percent probability of not stocking out on pepperoni. Assume that the sales representative just walked in the door and there are currently 470 pounds of pepperoni in the walk-in cooler. How many pounds of pepperoni would you order? (Use Excel's NORMSINV() function to find the correct critical value for the given a-level. Do not round intermediate calculations. Round "z" value to 2 decimal places and final answer to the nearest whole number.) X Answer is complete but not entirely correct. Amount of pepperoni's ordered 1,969 pounds