Write a program that will predict the size of a population of organisms. The program should ask the user for the starting number of organisms, their average daily population increase (as a percentage, expressed as a fraction in decimal form: for example 0.052 would mean a 5.2% increase each day), and the number of days they will multiply. A loop should display the size of the population for each day. Input Validation. Do not accept a number less than 2 for the starting size of the population. If the user fails to satisfy this print a line with this message "The starting number of organisms must be at least 2.", display the prompt again and try to read the value . Similarly, do not accept a negative number for average daily population increase , using the message "The average daily population increase must be a positive value ." and retrying. Finally, do not accept a number less than 1 for the number of days they will multiply and use the messag. The number of days must be at least 1.

Here is the C++ program:

#include<iostream>   // to use input output functions

using namespace std;   //to identify objects like cin cout

int main()  { // start of the main() function body

// holds the value for starting number of organisms and number of days

   int start_size, days;  

/* stores value of daily population increase. The data type is set to double to take value of population increase as a fraction */

   double pop_increase;  

//prompts user to enter starting no of organisms

   cout << "Enter the starting number of organisms: ";

   cin >> start_size;  //reads the value of starting number of organism

/* if the user enters start size value less than 2 this loop keeps executing until the user enters a value of start_size greater than or equal to 2*/

   while(start_size < 2){

//displays message for the user to enter a start_size greater or equal to 2

    cout<<"The starting number of organisms must be at least 2"<<endl;

    cout << "Enter a number greater than or equal to 2: ";

     cin >> start_size;     }   //reads the value of start_size entered by user

//prompts user to enter value for avg daily population increase

   cout << "\nEnter average daily population increase as percentage: ";

   cin >> pop_increase; //reads the value of population increase

/* if the user enters pop_increase value less than 0 this loop keeps executing until the user enters a positive value of pop_increase */

   while(pop_increase < 0){  

//prompts user to enter the valid positive value for population increase

       cout<<"The average daily population increase must be a positive value"<<endl;

  cout << "Please enter a positive value for population increase: ";

  cin >> pop_increase;     }  //reads the value of pop_increase from user

cout << "\nEnter the number of days: ";  //prompts  to enter number of days

   cin >> days;//reads the value of days input by user

/* if the user enters days value less than 1 this loop keeps executing until the user enters a value of days greater than or equal to 1*/

   while(days < 1){

//prompts user to enter a valid value for number of days

    cout<<"The number of days must be at least 1"<<endl;

    cout << "Please enter a number of days greater than or equal to 1: ";

    cin >> days;     }  //reads days input from user

//prints the message below

   cout<<"\nSize of population for each day is given below";  

   cout << "\nDay\t\tPopulation"<<endl;  

//prints the Day and Population separated by tab spaces

   for(int i = 1; i <= days; i++){  //loop displays size of population for each day

       start_size = start_size * (1 + pop_increase / 100.0);  

//calculates  size of population of organisms

//displays the values of i and start_size

       cout << i << "\t\t" << start_size << endl;     }   }

Explanation:

the loop variable i starts from 1 and this loop body stops to execute when the value of i exceeds the value of number of days. The loop body has a statement start_size = start_size * (1 + pop_increase / 100.0);   that computes the size of a population of organisms. The starting number of organism is multiplied by ( 1 + the increase in population) and this increase in population is divided by 100 to be expressed as a fraction. At the end, the result of this whole equation is stored in start_size variable. The last print statement prints the values of i and values of start_size computed by the above formula.

The screenshot of the program along with its output is attached.

answer; (& & );

bad internet connection lol