Answer:
Desired C++ Program with proper comment is given below
Step-by-step explanation:
#include<iostream> 
using namespace std; 
 
//main function 
int main() 
{ 
 int totalMiles = 0; 
 int remainingMiles = 0; 
 double amt = 0; 
 
 //taking input from user regarind total miles 
 cout<<"Enter the total miles: "<<endl; 
 cin>>totalMiles; 
 //if-else condition to do the calculation 
 if(totalMiles<=100) 
 { 
 amt = totalMiles*.25; 
 } 
 else 
 { 
 remainingMiles = totalMiles - 100; 
 amt = 100*.25 + remainingMiles*.15; 
 } 
 
 cout<<"The total amount is: "<<amt<<endl; 
}