Q.Observe the following C++ code and answer the questions

Memory Management: A First Look

Think of your computer as a desk where you work. You have a limited surface area — that's your computer's physical memory (RAM). You can only keep a few books, papers, and tools on the desk at once. But the work you want to do might require many more items than the desk can hold. Memory management is the system that decides what stays on the desk, what gets put away in a drawer (the hard drive), and how to bring things back when you need them — all without you having to think about it.

The Precise Meaning

Memory management is the process by which an operating system controls and coordinates computer memory. It assigns portions of memory to running programs (called processes), tracks which parts of memory are in use and which are free, and decides what to do when programs need more memory than is physically available.

The key job is this: every program and every piece of data needs a place in memory to exist, and the operating system must give each one a spot without letting them interfere with each other.

Why It Matters

Without memory management, your computer would crash the moment you opened a second application. One program could accidentally overwrite another's data, or a program could claim all the memory and leave nothing for the rest of the system. Memory management makes multitasking possible — it lets you have a browser, a word processor, and a music player all running at once, each believing it has its own private memory space.

How It Works in Simple Terms

The operating system does three fundamental things:

• Allocation — When a program starts, the OS gives it a block of memory. When the program finishes, the OS takes that memory back and marks it as available for other programs.
• Protection — Each program is given its own "sandbox" of memory. Program A cannot see or change the memory belonging to Program B. If it tries, the OS stops it and usually terminates the offending program.
• Virtual memory — When programs need more memory than the physical RAM can provide, the OS uses a portion of the hard drive as an extension of memory. It moves less-used data from RAM to the hard drive (called swapping or paging) and brings it back when needed. This is why your computer can run large programs even if you have only 8 GB of RAM.

A Concrete Everyday Analogy

Imagine a small restaurant kitchen with only one counter (RAM). The chef is preparing five different dishes at once. The counter can only hold three dishes' worth of ingredients at a time. The chef keeps the remaining ingredients in the storeroom (hard drive). When she needs to work on dish number four, she clears the counter, puts away the ingredients for dish number one, and brings out the ingredients for dish number four. She never mixes ingredients from different dishes on the same plate — each dish has its own section of the counter. That is memory management in action. …

Function Call Handling

Think about what happens when you ask a friend for a favour. You stop what you're doing, explain what you need, and then wait while your friend does the work. Once they finish, they come back to you with the result, and you resume whatever you were doing. That simple back-and-forth is the essence of how function calls work in programming.

The Everyday Intuition

Imagine you're cooking a meal. You have a recipe book open. The main recipe says "prepare the sauce" — but it doesn't list every single step for making the sauce right there. Instead, it expects you to know a separate sauce recipe. So you pause the main cooking, go make the sauce, and when it's ready, you return to the main dish and continue. The sauce recipe is like a function: a self-contained set of instructions that does one specific job.

In programming, a function call is exactly this: the main program says "go do this specific task," hands over any necessary information, waits for the task to complete, and then gets back whatever result the function produced.

The Precise Meaning

A function call is the instruction that tells the computer to execute a predefined block of code — the function — and then return control back to the point where the call was made. The function itself is a named, reusable set of instructions that performs a particular operation.

When a function is called, three things happen in sequence:

• The current task is paused — the computer remembers exactly where it was in the main program.
• Control is transferred to the function, along with any data the function needs to do its job (these are called arguments or parameters).
• The function runs its instructions, produces a result (if any), and returns control — along with that result — back to the exact spot where the call was made.

Why It Matters

Function call handling is not a trivial detail — it is the backbone of how programs are organised. Without it, every program would be one long, flat list of instructions, impossible to manage beyond a few dozen lines.

Here is why this concept is so important:

• Reusability — You write a function once and call it as many times as needed. The same "calculate tax" function can be called for every customer without rewriting the logic.
• Modularity — A program is broken into small, independent pieces. Each function does one thing well. This makes the program easier to understand, test, and fix.
• Abstraction — When you call a function, you do not need to know how it works internally. You only need to know what it does and what information to give it. This is like driving a car without understanding the engine.
• Readability — A program that uses function calls reads almost like an outline: "process order, calculate discount, send confirmation." Each step is a function name that describes what happens.

How the Computer Keeps Track …