A online retailer has hired you to write a program to calculate the total cost of a customer's order. First, the retailer must enter the name and the price per unit for two different candies. Then, the customer is allowed to order as many units of each of the two candies as they would like. Lastly, an invoice (report) is generated (displayed to the screen under the following rules: 1. All units up to and including the 20th are sold at full price. 2. All unit in excess of 20 are sold at a 10% discount. 3. For each candy there must be a separate line indicating: The candy's name The candy's full unit price How many units are being sold at full unit price The resulting subtotal And if applicable, another line indicating The candy's name o The candy's discounted unit price How many units are being sold at discounted unit price The resulting subtotal 4. There must be a line indicating the total of the order. 5. There must be a line indicating the sales tax on the total of the order (based on a 5% sales tax) 6. There must be a line indicating the grand total of the order. Outline: 1 Create a text file in your UNIX account programo9.c 2. Edit your programm09.c file to contain your C source code Save your programog.c file 4 Compile your program09.c file (repeating steps 2-4 until it compiles without error Run/Test the resulting aout file A You really need to run your program a number of times to do this thoroughly