The number of different $$n \times n$$ symmetric matrices with each elements being either $$0$$ or $$1$$ is

Consider the following statements with respect to user-level threads and kernel-supported threads.
i) Context switch is faster with kernel- supported threads
ii) For user-level threads, a system call can block the entire process
iii) Kernel-supported threads can be scheduled independently
iv) Use-level threads are transparent to the kernel

Which of the above statements are true?

Consider the following set of processes, with the arrival times and the $$CPU$$-burst times given in milliseconds.

What is the average turnaround time for these processes with the preemptive shortest remaining processing time first $$(SRTF)$$ algorithm?

Consider a program $$P$$ that consists of two source modules $${M_1}$$ and $${M_2}$$ contained in two different files. If $${M_1}$$ contains a reference to a function defined in $${M_2}$$, the reference will be resolved at.