What is the maximum number of reduce moves that can be taken by a bottom-up parser for a grammar with no epsilon and unit-production ( i.e., of type $$A \to \varepsilon $$ and $$A \to a$$ ) to parse a string with n tokens?

Consider the following two sets of LR(1) items of an LR(1) grammar.

$$\eqalign{ & X \to c.X,\,c/d\,\,\,\,\,\,\,\,X \to c.X,\$ \cr & X \to .cX,c/d\,\,\,\,\,\,\,\,X \to .cX,\$ \cr & X \to .d,c/d\,\,\,\,\,\,\,\,\,\,\,X \to .d,\$ \cr} $$

Which of the following statements related to merging of the two sets in the corresponding LALR parser is/are FALSE?

1. Cannot be merged since look aheads are different.
2. Can be merged but will result in S-R conflict.
3. Can be merged but will result in R-R conflict.
4. Cannot be merged since goto on c will lead to two different sets.

Assume that source S and destination D are connected through two intermediate routers labeled R. Determine how many times each packet has to visit the network layer and the data link layer during a transmission from S to D.

Determine the maximum length of cable (in km) for transmitting data at a rate of 500 Mbps in an Ethernet LAN with frames of size 10,000 bits. Assume the signal speed in the cable to be 2,00,000 km/s