51.
User level threads are threads that are
visible to the programmer and are unknown to the kernel. The operating system
kernel supports and manages kernel level threads. Three different types of
models relate user and kernel level threads.

Which of the
following statements is/are true?

(a) (i) The
Many - to - one model maps many user threads to one kernel thread

(ii) The one - to - one model maps one
user thread to one kernel thread

(iii) The many - to - many model maps many
user threads to smaller or equal kernel

threads

(b) (i) Many - to - one model maps many kernel
threads to one user thread

(ii) One - to - one model maps one kernel
thread to one user thread

(iii) Many - to - many model maps many
kernel threads to smaller or equal user

threads

**Code :**

(1) (a) is
true; (b) is false

(2) (a) is
false; (b) is true

(3) Both (a)
and (b) are true

(4) Both (a)
and (b) are false

Answer: 1

52. Consider
a system with five processes P0 through P4 and three resource types A, B and C.
Resource type A has seven instances, resource type B has two instances and
resource type C has six instances suppose at time T0 we have the following
allocation.

If we
implement Deadlock detection algorithm we claim that system is
..................

(1)
Semaphore

(2) Deadlock
state

(3) Circular
wait

(4) Not in
deadlock state

Answer: Marks to all

53. Consider
a disk queue with requests for I/O to blocks on cylinders 98, 183, 37, 122, 14,
124, 65, 67. Suppose SSTF disk scheduling algorithm implemented to meet the
requests then the total number of head movements are ................... if the
disk head is initially at 53.

(1) 224

(2) 248

(3) 236

(4) 240

Answer: 3

54. The
Bounded buffer problem is also known as ..................

(1) Producer
- consumer problem

(2) Reader -
writer problem

(3) Dining
Philosophers problem

(4) Both (2)
and (3)

Answer: 1

55. In
Artificial Intelligence (AI), which agent deals with happy and unhappy state?

(1) Simple
reflex agent

(2) Model
based agent

(3) Learning
agent

(4) Utility
based agent

Answer: 4

56. If
b is the branching factor and m is the maximum depth of the search tree, what
is the space complexity of greedy search?

(1) O(b+m)

(2) O(bm)

(3) O(b

^{m})
(4) O(m

^{b})
Answer: 3

57. Let
P, Q, R and S be Propositions. Assume that the equivalences P⇔(Q∨¬Q) and Q⇔R hold. Then the truth value of the formula
(P∧Q)⇒((P∧R)∨S) is always :

(1) True

(2) False

(3) Same as
truth table of Q

(4) Same as
truth table of S

Answer: 1

58. “If
X, then Y unless Z” is represented by which of the following formulae in
propositional

logic?

(1) (X ∧ Y) → ¬ Z

(2) (X ∧ ¬ Z) → Y

(3) X → (Y ∧ ¬ Z)

(4) Y → (X ∧ ¬ Z)

Answer: 2

59. Consider
the following two well-formed formulas in prepositional logic.

F1 : P ⇒ ¬ P

F2 : (P ⇒ ¬ P) ∨ (¬ P ⇒ P)

Which of the
following statements is correct?

(1) F1 is
Satisfiable, F2 is valid

(2) F1 is
unsatisfiable, F2 is Satisfiable

(3) F1 is
unsatisfiable, F2 is valid

(4) F1 and
F2 both are Satisfiable

Answer: 1

60. Standard
planning algorithms assume environment to be .................

(1) Both
deterministic and fully observable

(2) Neither
deterministic nor fully observable

(3)
Deterministic but not fully observable

(4) Not
deterministic but fully observable

Answer: 1

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