MBOSE Class 11 Question Paper 2020 for Computer Science

Total No. of Printed Pages ––9 (2)
HS/XI/A.Sc.Com./CS/20
(ii) What will be the output of the following
expression?
2020 a =10
b=4
COMPUTER SCIENCE
c=a%b
( Theory )
(a) 2.5

(b) 2.0
Full Marks : 70
Time : 3 hours (c) 2

(d) 3.0

The figures in the margin indicate full marks for the questions
(iii) Write the for statement to generate the following
General Instructions : series.
2 4 6 8 10
(i) Write all the answers in the Answer Script.
(a) for i in range (2 to 10, 2):
(ii) Attempt all the questions. (b) for i in range (2 to 11, 2):

(c) for i in range (2, 10, 2):
1. Choose the correct answer from the following 1 6  6 (d) for i in range (2, 11, 2):
(i) Which of the following is not mutable types?
(iv) _______ are small data holding areas within CPU
(a) List that hold data, instructions and memory address
during Processing.
(b) Tulpe (a) RAM chips

(c) Dictionary (b) CD-ROMs

(c) SoC chips
(d) Sets.
(d) Registers.

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(3) (4)

(v) Which of the following key is used to represent (v) What is a database system?
the relationship between two tables?
(vi) What is Cyber Safety?
(a) Primary Key

(b) Foreign Key
3. Answer the following questions in brief: 2  6  12
(c) Alternate Key
(i) What are operators? What are their functions?
(d) Candidate Key
(ii) What are floating numbers? When are they
preferred over integers?
(vi) _______ is a small piece of data sent from a website
and stored in a user’s web browser while a user (iii) What is entry-controlled loop? Give one example.
is browsing a Website.
(iv) Differentiate between a syntax error and logical
(a) spam error in a program.
(b) viruses (v) What will be the output of the following
(c) cookies expression?

(d) Digital Footprint (a) ‘MYSTRY” [:4]

(b) “pine’’ in “Pineapple”

2. Answer the following questions in not more than two (vi) How are individual elements of Dictionaries
sentences: 1 6  6 accessed?
(i) What are literals in Python?

(ii) What is the significance of pass statement in 4. Answer the following: 33  9
Python?
(i) What are the built-in core data types of Python?
(iii) What are Python Lists? What are Numeric types? How many numeric
(iv) What is Unicode? data types does Python provide? 3

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(5) (6)

(ii) Write the output of the following code fragments: 3 Or
x = 15 Write a Python program to input three integers
and find out the largest integer. 4
y=5
while x>y :
(ii) Write a Python program to sort a list of integers
print (x, y)
using Bubble sort. 4
x=x–2
Or
y=y+2
Explain get ( ) and update ( ) methods of Dictionary
Or
with examples. 4
Explain the if-else statement with example 3

6. Answer the following questions : 2 2  4
(iii) Write a program that asks the user to input a
year and to find out whether it is a leap year or (i) What is the function of main memory? What are
not. 3 the measuring units of memory? 2
Or
(ii) What are De Morgan’s theorems? 2
What will be the output of the following code
fragment 3 Or
tl = (4, 5, 6) Prove the following Boolean expression: 2
t2 = (6, 7) A(B  B' C  B' C' )  A
t3 = tl + t2
t4 = t2 + t3
7. Draw a block diagram depicting organization of a mobile
Print (t3) system. 4
Print (t4) Or
Convert the following: 2+2=4
5. Answer the following: 42  8
(a) (1876.B4)16 to Binary
(i) What is the difference between append ( ) and
insert ( ) methods of list. Explain with examples. 4 (b) (110010.101)2 to Decimal.

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(7) (8)

8. Answer the following : 23  6 Or
Consider the following TEACHER table and write SQL
(i) Write two advantages of using database. 2 commands for the following queries. 4

(ii) Differentiate between Char and Varchar TNO TNAME SALARY DEPT DOJ
Datatypes. 2
T01 VARUN 25000 PHYSICS 2000/01/01
(iii) What is Primary Key? What is Primary Key SHARMA
constraint? 2
TO2 RUPAK 25700 COMPUTER 1999/01/05
DAS SCIENCE

9. Write the purpose and example of each MYSQL T03 MITALE 30000 COMPUTER 2001/10/01
function. 3 1  3 BARUA SCIENCE

(a) Upper ( ) T04 SHYAMA 24000 CHEMISTRY 2000/02/07
DUTTA
(b) NOW ( )
(a) Display all records from the table TEACHER.
(c) LTRIM ( )
(b) Display all records whose SALARY is more
Or than 25000.

(c) Display the NAME and SALARYof the
What are table constraints? What are column teachers whose DEPT is COMPUTER
constraints? How does these two differ? 1+1+1=3 SCIENCE.

(d) Insert a new row in the TEACHER table with
following data:
10. What is NOSQL database? What are its main features?
List name of four types of NOSQL Databases. T05, SUMAN SINHA, 25200,
1+2+1=4 CHEMISTRY, 2001/04/01.

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(9)

11. Answer the following questions:

(i) What is Cyber bullying and Cyber stalking? 2

(ii) What are different types of threats to computer
security? Explain any one of them. 1+2=3

(iii) What is phishing? How is pharming similar to
and different from phishing? 1+1+1=3



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