4. Write an interactive C program that calculates a customer's bill for mobile telecommunication company. There are two types of customers residential and business. There are two rates for calculating a bill: one for residential customers and one for business customers. For residential customers, the following rates apply: Bill processing fee: GHC3.50 Basic service fee: GHC10.50 Premium channels: GHC8.50 per channel For business customers, the following rates apply: Bill processing fee: GHC12.00 Basic service fee: GHC20.00 for the first 20 connections, GHC4.00 for each additional connection Premium channels: GHC40 per channel for any number of connections The program should ask the user for an account number (an integer) and a customer code Assume that a customer code 100 stands for a residential customer, and 200 stands for a business customer. loput: The customer's account number, customer code, number of premium channels to which the user subscribes, and, in the case of business customers, number of basic service connections. 18 marks] Processing: The program should use the following functions to calculate and return the billing amount Residentialbi17: This function calculates and returns the billing amount for residential service 112 marks EXAMINER: WIAFE OWUSU-BANAHENE (PHD) Page 3 of 4 Business8177: This function calculates and returns the billing amount for business service [10 marks) Output: Customer's account number, the type of service and the billing amount