For a statement S in a program, in the context of liveness analysis, the following sets are defined:

USE(S): the set of variables used in S

IN(S): the set of variables that are live at the entry of S

OUT(S): the set of variables that are live at the exit of S

Consider a basic block that consists of two statements, S₁ followed by S₂.

Which one of the following statements is correct?

Consider the three-way handshake mechanism followed during TCP connection establishment between hosts P and Q. Let X and Y be two random 32-bit starting sequence numbers chosen by P and Q respectively. Suppose P sends a TCP connection request message to Q with a TCP segment having SYN bit = 1, SEQ number = X, and ACK bit = 0. Suppose Q accepts the connection request. Which one of the following choices represents the information present in the TCP segment header that is sent by Q to P?

Consider a computer network using the distance vector routing algorithm in its network layer. The partial topology of the network is as shown below.

The objective is to find the shortest-cost path from the router R to routers P and Q. Assume that R does not initially know the shortest routes to P and Q. Assume that R has three neighbouring routers denoted as X, Y, and Z. During one iteration, R measures its distance to its neighbours X, Y, and Z as 3, 2, and 5, respectively. Router R gets routing vectors from its neighbours that indicate that the distance to router P from routers X, Y, and Z are 7, 6, and 5, respectively. The routing vector also indicates that the distance to router Q from routers X, Y, and Z are 4, 6, and 8, respectively. Which of the following statement(s) is/are correct with respect to the new routing table of R, after updation during this iteration ? 

Consider the cyclic redundancy check (CRC) based error detecting scheme having the generator polynomial X³ + X + 1. Suppose the message m₄m₃m₂m₁m₀ = 11000 is to be transmitted. Check bits c₂c₁c₀ are appended at the end of the message by the transmitter using the above CRC scheme. The transmitted bit string is denoted by m4m3m2m1m0c2c1c0. The value of the check bit sequence c2c1c0 is