Trench 4 foot or deeper and must be located 25 foot within eachother
        
                    
             
        
        
        
Answer:
The expression is :
π[cd) + π(g,h) ],[π(e,f)+π(a,b)])
We will use foreign key and primary key
 
        
             
        
        
        
Answer:
The function is as follows:
void readAndConvert(){
    int n; string symbol,name;
    cin>>n;
    cin>>symbol;
    cin.ignore();
    getline (cin,name);
    vector<string> trades;
    string trade;
    for (int inps = 0; inps < n; inps++){
        getline (cin,trade);
        trades.push_back(trade);}
    
    cout<<name<<" ("<<symbol<<")"<<endl;
    for (int itr = 0; itr < n; itr++){
        string splittrade[3];        int k = 0;
        for(int j=0;j<trades.at(itr).length();j++){
            splittrade[k] += trades.at(itr)[j];
            if(trades.at(itr)[j] == ' '){
                k++;    }}
cout<<splittrade[2]<<": "<<floor(stod(splittrade[1]) * stod(splittrade[0]))<<endl;        }
    }
Explanation:
See attachment for complete program where comments are used to explain each line