Emma should include the directive #include at the beginning of her program to access the cout and cin objects without qualifying them with std::. This directive provides access to the standard I/O stream objects.

You would use a do-while loop over a while loop when you want to ensure that the loop body is executed at least once, regardless of whether the initial condition is true or false. The condition is checked after the first execution in a do-while loop.

If a function is declared but not defined in a program, it will result in a linker error during the linking phase. This error occurs because the linker cannot find the actual implementation of the function, and therefore, it cannot resolve references to that function.

Samantha can use the break statement to efficiently exit out of multiple nested loops upon a particular condition. When the break statement is encountered, it terminates the innermost loop and continues executing the code after the loop. It's important to use this construct judiciously to avoid unexpected behavior.

In C++, the "if" keyword is used to define a condition. It's a fundamental control structure for conditional execution in the language. You use "if" to specify a condition that, if true, executes a block of code.

The inline keyword is used before a function in C++ to make it an inline function. An inline function is a request to the compiler to insert the code of the function at the calling point instead of performing a normal function call. This can improve performance in certain situations by reducing the overhead of function calls.

In scenarios where a loop's execution depends on an external condition, the while loop is most appropriate. It evaluates the condition before each iteration, allowing you to control the loop based on changing external conditions.

Inline functions in C++ are a type of compiler optimization. When you declare a function as inline, you suggest to the compiler that it should insert the code of that function directly into the caller's code, avoiding the overhead of a regular function call. This can lead to better performance in some cases.

Emily should use a For Loop to calculate the factorial of a number. A For Loop is well-suited for tasks where you know in advance how many iterations are required, as is the case with factorial calculations. She can initialize the loop variable, set the loop condition to run until the variable reaches 1, and decrement the variable in each iteration to multiply the numbers in a descending order.

To get the correct result, Jake should add 5 and 7 first and then multiply the result by 3. The expression (5 + 7) * 3 achieves this, providing the correct answer of 36.