Computer Science · Sample Paper 2

General instructions

Section A · Objective

1. Question 11 mark

   Which unit of the CPU performs arithmetic and logical operations?

   1. A.CU
   2. B.ALU
   3. C.register
   4. D.cache
2. Question 21 mark

   1 terabyte is equal to

   1. A.1024 GB
   2. B.1000 MB
   3. C.1024 MB
   4. D.1024 KB
3. Question 31 mark

   $(25{)}_{10}$ in binary is

   1. A.11001
   2. B.10011
   3. C.11010
   4. D.10101
4. Question 41 mark

   $(745{)}_8$ in decimal is

   1. A.485
   2. B.475
   3. C.493
   4. D.501
5. Question 51 mark

   How many bits are used in standard ASCII?

   1. A.7
   2. B.8
   3. C.16
   4. D.32
6. Question 61 mark

   Delivering computing resources like storage and software over the internet is called

   1. A.IoT
   2. B.cloud computing
   3. C.AI
   4. D.blockchain
7. Question 71 mark

   Which of these is the first step of problem solving?

   1. A.coding
   2. B.analysing the problem
   3. C.testing
   4. D.debugging
8. Question 81 mark

   What is the output of print(type(3.0))?

   1. A.<class 'int'>
   2. B.<class 'float'>
   3. C.<class 'str'>
   4. D.<class 'complex'>
9. Question 91 mark

   Which operator is used for exponentiation in Python?

   1. A.^
   2. B.**
   3. C.//
   4. D.%
10. Question 101 mark

    What is the output of print(10 - 4 * 2 + 1)?

    1. A.13
    2. B.3
    3. C.6
    4. D.9
11. Question 111 mark

    What is printed?

    x = 7
    if x > 5:
        print('A')
    elif x > 3:
        print('B')
    else:
        print('C')
    

    1. A.A
    2. B.B
    3. C.C
    4. D.A B
12. Question 121 mark

    range(5) generates

    1. A.1 to 5
    2. B.0 to 5
    3. C.0 to 4
    4. D.1 to 4
13. Question 131 mark

    Which keyword is used to define a function in Python?

    1. A.function
    2. B.def
    3. C.fun
    4. D.define
14. Question 141 mark

    What is the output of print('ab' * 3)?

    1. A.ab3
    2. B.ababab
    3. C.ab ab ab
    4. D.error
15. Question 151 mark

    If s = 'Computer', what is s[-3:]?

    1. A.'Com'
    2. B.'ter'
    3. C.'ute'
    4. D.'r'
16. Question 161 mark

    L = [10, 20, 30, 40]. What is L[1:3]?

    1. A.[10, 20]
    2. B.[20, 30]
    3. C.[20, 30, 40]
    4. D.[30, 40]
17. Question 171 mark

    L = [3, 1, 2]; L.sort(reverse=True). What is L?

    1. A.[1, 2, 3]
    2. B.[3, 2, 1]
    3. C.[3, 1, 2]
    4. D.None
18. Question 181 mark

    Which method returns all keys of a dictionary d?

    1. A.d.values()
    2. B.d.keys()
    3. C.d.items()
    4. D.d.get()
19. Question 191 mark

    Software whose source code is freely available to modify and share is

    1. A.proprietary software
    2. B.open-source software
    3. C.shareware
    4. D.malware
20. Question 201 mark

    Assertion (A): Lists in Python are mutable.

    Reason (R): Elements of a list can be changed after it is created, e.g. L[0] = 5.

    1. A.Both Assertion (A) and Reason (R) are true, and R is the correct explanation of A.
    2. B.Both Assertion (A) and Reason (R) are true, but R is not the correct explanation of A.
    3. C.Assertion (A) is true, but Reason (R) is false.
    4. D.Assertion (A) is false, but Reason (R) is true.
21. Question 211 mark

    Assertion (A): A tuple can contain a list as an element.

    Reason (R): Tuples are mutable.

    1. A.Both Assertion (A) and Reason (R) are true, and R is the correct explanation of A.
    2. B.Both Assertion (A) and Reason (R) are true, but R is not the correct explanation of A.
    3. C.Assertion (A) is true, but Reason (R) is false.
    4. D.Assertion (A) is false, but Reason (R) is true.

Section B · Very short answer

1. Question 222 marks

   What is an operating system? Give two of its functions.

2. Question 232 marks

   Convert $(10110110{)}_2$ to hexadecimal and $(3A{)}_{16}$ to decimal.

3. Question 242 marks

   Write the output:

   x = 5
   y = x * 2
   x += 3
   print(x, y)
   print(x > y or x == 8)
   

4. OR

   Question 242 marks

   Differentiate between = and == in Python with an example.

5. Question 252 marks

   Write the output:

   for i in range(1, 10, 2):
       if i == 7:
           break
       print(i, end=' ')
   

6. Question 262 marks

   Write the output:

   s = 'python program'
   print(s.title())
   print(s.count('o'))
   

7. Question 272 marks

   Write the output:

   L = [1, 2, 3]
   L.extend([4, 5])
   L.insert(0, 9)
   print(L)
   print(L.index(3))
   

8. Question 282 marks

   What is cyberbullying? Give two ways to deal with it.

Section C · Short answer

1. Question 293 marks

   Write a Python program to print the sum of the digits of a number entered by the user.

2. OR

   Question 293 marks

   Write a Python program to check whether a number entered by the user is prime.

3. Question 303 marks

   What is decomposition in problem solving? Write an algorithm to find the average of n numbers.

4. Question 313 marks

   Write the output:

   t = (1, 2, 3, 2, 4)
   print(t.count(2), t.index(4))
   d = {1: 'a', 2: 'b'}
   for k, v in d.items():
       print(k, v)
   print(len(d))
   

Section D · Long answer

1. Question 324 marks

   Write a function is_armstrong(n) that returns True if n is an Armstrong number (e.g. 153 = 1³ + 5³ + 3³) and use it to print all 3-digit Armstrong numbers.

2. Question 334 marks

   Write a program that reads a sentence and prints the number of vowels, consonants, digits and spaces in it.

3. OR

   Question 334 marks

   Write a program that reads a sentence and prints the longest word in it and its length.

4. Question 344 marks

   Write a program to find the second largest number in a list without using sort().

5. Question 354 marks

   Explain (i) artificial intelligence (ii) blockchain (iii) big data (iv) virtual reality, with one application each.

Section E · Long answer

1. Question 365 marks

   Write a program to input names and marks of n students into a dictionary and display (i) the student with the highest marks (ii) the names of students who scored more than 75.

2. OR

   Question 365 marks

   Write a program that reads n numbers into a list and then (i) removes all duplicates, keeping the first occurrence, (ii) prints the list in ascending order, (iii) prints the mean.

3. Question 375 marks

   What is e-waste? Explain its hazards and the methods of managing it. Also state two provisions of the IT Act, 2000.