Help with the following questions of Operating Systems

1. Explain the concept of Interprocess Communication (IPC). Compare and contrast the two main methods of IPC: shared memory and message passing. What is the role of sockets in IPC and what type of IPC mechanism (of the two above) do they represent?
2. Explain the concept of system calls and how they work in an OS. Give a concrete example of a task that requires multiple system calls to be called to complete in a modern computer system and identify which system calls would need to be called (potential tasks you could use include things like copying a file or reading a web page from a remote server).
3. Describe what a context switch is. Be sure to include different reasons that a context switch may occur in a system and what data within the system needs to be swapped out during the context switch. How does the data swapped out differ when switching between two threads within a single process and between two separate processes.