Question

Write a cout statement so the variable population is displayed in a field of 12 spaces, left-justified, with a precision of 8 decimal places. The decimal point should always be displayed.

Short answer

Answer: To display the "population" variable with the desired formatting, follow these steps: 1. Include the iostream and iomanip header files. 2. Declare a double-precision variable called "population" and assign a value to it. 3. Activate the left-justification using the "left" function from the iomanip header. 4. Set the field width to 12 spaces and the precision to 8 decimal places using "setw()" and "setprecision()" functions from the iomanip header. 5. Display the "population" variable using a cout statement. Here's a complete example: ```cpp #include #include int main() { double population = 12345.678901; std::cout << std::left; std::cout << std::setw(12) << std::setprecision(8) << std::fixed; std::cout << population << std::endl; return 0; } ``` This code will output the "population" value with the desired format: 12345.67890100 in a field of 12 spaces, left-justified, with 8 decimal places.

Step-by-step solution

Include the necessary header files.

First, we need to include the iostream and iomanip header files, which are required for using cout, setprecision, and setw functions. ```cpp #include #include ```

Create a variable named "population."

Declare a double-precision variable called "population" and assign a value to it. In this case, we will use a sample value of 12345.678901. ```cpp double population = 12345.678901; ```

Activate the left-justification.

Before displaying the "population" variable, we need to activate the left-justification using the "left" function from the iomanip header. ```cpp std::cout << std::left; ```

Set the field width and precision.

Next, using the "setw()" function from the iomanip header, set the field width to 12 spaces, and then use the "setprecision()" function from the same header, to set the precision to 8 decimal places. ```cpp std::cout << std::setw(12) << std::setprecision(8); ```

Display the value of the "population" variable.

With the left-justification, field width, and precision settings in place, use the cout statement to display the "population" variable. ```cpp std::cout << population << std::endl; ```

Complete code

The complete code for displaying the "population" variable with the desired formatting should look like this: ```cpp #include #include int main() { double population = 12345.678901; std::cout << std::left; std::cout << std::setw(12) << std::setprecision(8) << std::fixed; std::cout << population << std::endl; return 0; } ``` This code will output the desired format: 12345.67890100 in a field of 12 spaces, left-justified, with 8 decimal places.