Based on coding shown, what header that should be use?

​int main() {

double x = 4.5;
double squareRoot = sqrt(x);
double cosineValue = cos(x);

cout << "Square root of " << x << " is " << squareRoot << endl;
cout << "Cosine of " << x << " is " << cosineValue << endl;

char ch = 'A';
bool isUpper = isupper(ch);
bool isDigit = isdigit(ch);

cout << ch << " is uppercase? " << boolalpha << isUpper << endl;
cout << ch << " is a digit? " << boolalpha << isDigit << endl;
return 0;

}

Create a C++ coding that create a menu using function

// Function to display the menu options
void displayMenu() {
cout << "=== Menu ===" << endl;

cout << "1. Option 1" << endl;

cout << "2. Option 2" << endl;

cout << "3. Option 3" << endl;

cout << "4. Quit" << endl;

cout << "=============" << endl;

}

​Function

int main() {

int choice;

do {

displayMenu();

cout << "Enter your choice (1-4): ";

cin >> choice;

switch (choice) {

case 1: cout << "You selected Option 1." << endl; break;

case 2: cout << "You selected Option 2." << endl; break;

case 3: cout << "You selected Option 3." << endl; break;

case 4: cout << "Quitting the program." << endl; break;

default: cout << "Invalid choice. Please try again." << endl; break;

}

cout << endl;

} while (choice != 4); return 0; }

​Main Function

Example code: