Let G be an arbitrary group. Consider the following relations on G :

R1: ∀a,b ∈ G, aR₁b if and only if ∃g ∈ G such that a = g^-1bg

R2: ∀a,b ∈ G, aR₂b if and only if a = b^-1

Which of the above is/are equivalence relation/relations?

The following C program is executed on a Unix/Linux system:

         #include < unistd.h >
            int main ()
            {
                  int i ;
                  for (i=0; i<10; i++)
                         if (i%2 == 0) fork ( ) ;
                  return 0 ;
            }

The total number of child processes created is _____.

Assume that in a certain computer, the virtual addresses are 64 bits long and the physical addresses are 48 bits long. The memory is word addressable. The page size is 8 kB and the word size is 4 bytes. The Translation Look-aside Buffer (TLB) in the address translation path has 128 valid entries. At most how many distinct virtual addresses can be translated without any TLB miss?

Consider the following four processes with arrival times (in milliseconds) and their length of CPU bursts (in milliseconds) as shown below :

These processes are run on a single processor using preemptive Shortest Remaining Time First scheduling algorithm. If the average waiting time of the processes is 1 millisecond, then the value of Z is _____.