$1.$ System call implementations look exactly the same on different OS's like Linux and Windows, e$.$g$.,$ a system call that reads from and I$/$O device. $2.$ During an interrupt, a bit allows a process to go from user mode into kernel mode $($privileged$)$ in order to run the code that handles the interrupt. $3.$ Which of the following describe a Symmetric Multiprocessing Architecture: $4.$ Polled interrupts are the same as vectored interrupts