Write a program to take orders for the Quad sandwich shop. The Quad sandwich shop sells sandwiches and salads. If a customer orders 3 or more items of the same type, there is a special price. The program should only accept sandwich or salad as valid choices. All other entries are invalid. Sandwiches cost $3.50 each or $2.75 for 3 or more. Salads cost $4.50 each or $3.75 for 3 or more. Using the following sample inputs, write a program that will correctly calculate a persons order. The output should be in US Dollars (so there needs to be the $ and it must display values to two decimal places). Be sure to document the variables, constants and the program source code. Submit the code and one screenshot.

please do in c++