Consider a complete undirected graph with vertex set {0,1,2,3,4}. Entry W_ij in the matrix W below is the weight of the edge {i, j} $$$W = \left( {\matrix{ 0 & 1 & 8 & 1 & 4 \cr 1 & 0 & {12} & 4 & 9 \cr 8 & {12} & 0 & 7 & 3 \cr 1 & 4 & 7 & 0 & 2 \cr 4 & 9 & 3 & 2 & 0 \cr } } \right)$$$ What is the minimum possible weight of a spanning tree T in this graph such that vertex 0 is a leaf node in the tree T?

A hash table of length 10 uses open addressing with hash function h(k)=k mod 10, and linear probing. After inserting 6 values into an empty hash table, the table is as shown below How many different insertion sequences of the key values using the same hash function and linear probing will result in the hash table shown above?

A relational schema for a train reservation database is given below:

Passenger ( pid, pname, age)
Reservation (pid, cass, tid)

Table: Passenger

pid	pname	age
0	'Sachin'	65
1	'Rahul'	66
2	'Sourav'	67
3	'Anil'	69

Table: Reservation

pid	class	tid
0	'AC'	8200
1	'AC'	8201
2	'SC'	8201
5	'AC'	8203
1	'SC'	8204
3	'AC'	8202

What pids are returned by the following SQL query for the above instance of the tables?

SELECT   pid
FROM   Reservation
WHERE   class 'AC' AND 
EXISTS (SELECT * 
FROM Passenger 
WHERE age > 65 
AND Passenger.pid = Reservation.pid);

Which of the following concurrency control protocols ensure both conflict serializability and freedom from deadlock?

I. 2-phase locking
II. Time-stamp ordering