Class 12 CS 083 Previous Year Question Paper 2025 Soution

Series ZYW1X
Question Paper Code 91 Set 4

COMPUTER SCIENCE – Solution Updating…
(Session 2024-25)

Time allowed : 3 hours
Maximum Marks : 70

General Instructions :

1. This question paper contains 37 questions and five sections, Section A to E.
2. All questions are compulsory.
3. Section A have 21 questions carrying 1 mark each.
4. Section B has 7 Very Short Answer type questions carrying 2 marks each.
5. Section C has 3 Short Answer type questions carrying 3 marks each.
6. Section D has 4 Long Answer type questions carrying 4 marks each.
7. Section E has 2 questions carrying 5 marks each.
8. All programming questions are to be answered using Python Language only.
9. In case of MCQs, text of the correct answer should also be written.
   

SECTION – A (21×1=21)

1. State True or False:
“A Python list must always contain all its elements of Same data type.”
Ans: False

2. What will be the output of the following statement?
print (14%3**2*4)
(a) 16
(b) 64
(c) 20
(d) 256

3. Identify the correct output of the following code snippet.
game="Olympic2024"
print(game.index("C"))
(a) 0
(b) 6
(c) -1
(d) ValueError

4. Which of the following is the correct identifier?
(a) global
(b) Break
(c) def
(d) with

5. Identify the invalid Python statement out of the following options.
(a) print("A",10,end="*")
(b) print("A",sep="*",10)
(c) print("A",10,sep="*")
(d) print("A"*10)

6. Consider the statements given below and then choose the correct output from the given options:
L=['TIC,'TAC']
print(L[::-1])
(a) ['CIT', 'CAT']
(b) ['TIC', 'TAC']
(c) ['CAT', 'CIT']
(d) ['TAC', 'TIC']

7. Which of the following operator evaluates to True if the variable on either side of the operator points towards the same memory location and False otherwise?
(a) is
(b) is not
(c) and
(d) or

8. Consider the statements given below and then choose the correct output from the given options:
D={'S01':95, 'S02':96}
for I in D :
print(I, end='#')
(a) S01#S02#
(b) 95#96#
(c) S01,95#S02,96#
(d) S01#95#S02#96#

9. While creating a table, which constraint does not allow insertion of duplicate values in the table?
(a) UNIQUE
(b) DISTINCT
(c) NOT NULL
(d) HAVING

10. Considere the statements given below and then choose the correct output from the given options:
def Change(N):
N=N+10
print(N,end='$$')
N=15
Change(N)
print(N)
(a) 25$$15
(b) 15$$25
(c) 25$$25
(d) 2525$$

11. Considere the statements given below and then choose the correct output from the given options:
N='5'
try:
print('WORD' +N, end='#')
except:
print('ERROR', end='#')
finally:
print('OVER')
(a) ERROR#
(b) WORD5#OVER
(c) WORD5#
(d) ERROR#OVER

12. Which of the following built-in function / method returns or dictionary?
(a) dict()
(b) keys()
(c) values()
(d) items()

13. Which of the following is a DML command in SQL?
(a) UPDATE
(b) CREATE
(c) ALTER
(d) DROP

14. Which aggregate function in SQL displays the number of values in the specified column ignoring the NULL values?
(a) len()
(b) count()
(c) number()
(d) num()

15. In MYSQL, which type of value should not be enclosed within quotation marks?
(a) DATE
(b) VARCHAR
(c) FLOAT
(d) CHAR

16. State True or False:
If table A has 6 rows and 3 columns, and table B has 5 rows and 2 columns, the Cartesian product of A and B will have 30 rows and 5 columns.
Ans: True

17. Which of the following networking devices is used to regenerate and transmit the weekend signal ahead?
(a) Hub
(b) Ethernet Card
(c) Repeater
(d) Modem

18. Which of the following options is the correct protocol used for phone calls over the internet?
(a) PPP
(b) FTP
(c) HTTP
(d) VoIP (Voice Over Internet Protocol)

19. Expand ARPANET.
Ans: Advanced Research Projects Agency Network

20. Assertion (A) : For a binary file opened using ‘rb’ mode, the pickle.dump() method will display and error.
Reason (R) : The pickle.dump() method is used to read from a binary file.
(a) Both (A) and (R) are true and (R) is the correct explanation for (A).
(b) Both (A) and (R) are true and (R) is not the correct explanation for (A).
(c) (A) is true and (R) is false.
(d) (A) is false but (R) is true.

21. Assertion (A) : We can retrieve records from more than one table in MYSQL.
Reason (R) : Foreign key is used to establish a relationship between two tables.
(a) Both (A) and (R) are true and (R) is the correct explanation for (A).
(b) Both (A) and (R) are true and (R) is not the correct explanation for (A).
(c) (A) is true and (R) is false.
(d) (A) is false but (R) is true.
Without foreign keys, managing relational data would be difficult.

SECTION – B (7×2=14)

22. What does return statement do in function? Explain with the help of an example.

23. Write one example of each of the following Python:
(i) Syntex error
Asn: print("Hello World"
(ii) Implicit type conversion
Ans: a = 10
b = 2.5
c = a + b
print(c)
print(type(c))
Implicitly converts a from int to float before performing the addition

24. Consider the following dictionaries, D and D1:
D={"Suman":40, "Raj":55, "Raman":60)
D1{"Aditi":30, "Amit":55, "Raj":60)
(Answer using built-in Python functions only)

(i) (a) Write a statement to display/return the value corresponding to the key “Raj” in the dictionary D.

OR

(b) Write a statement to display the length of the dictionary D1.

(ii) (a) Write a statement to append all the key-value pairs of the dictionary D to the dictionary D1.

OR

(b) Write a statement to delete the items with the given key “Amit” from the dictionary D1.

25. What possible output from the given options is expected to be displayed when the following code is executed?
import random
Cards=["Heart","Spade","Club","Diamon"]
for i in range(2):
print(Cards[random.randint(1,i+2)],end="#')
(a) Spade#Diamond#
(b) Spade#Heart#
(c) Diamond#Club#
(d) Heart#Spade#

26. The code given below accepts N as an integer argument and returns the sum of all integers from 1 to N. Observe the following code carefully and rewrite it after removing all Syntax and logical errors. Underline all the corrections made.
def SUM(N)
for I in range(N):
S=S+I
return S
print (Sum(10)

27. Nisha is assigned the task of maintaining the staff data of an organisation. She has to store the details of the staff in the SQL table named EMPLOYEES with attribute as EMONO, NAME, DEPARTMENT, BASICSAL to store Employee’s Identification Number, Name, Department and Basic Salary respectively. There can be two or more employees with the same name in the organisation.

(i) (a) Help Nisha to identify the attribute which should be designated as the primary key. Justify your answer.

OR

(b) Help Nisha to identify the constraint which should be applied to the attribute NAME such that the employees’ Name cannot be left empty or NULL while entering the records but can have duplicate values.

(ii) (a) Write the SQL command to change the size of the attribute BASICSAL in the table EMPLOYEES to allow the maximum value of 99999.99 to be stored in it.

OR

(b) Write the SQL command to delete the table EMPLOYEES.

28. (a) Expand and explain the term URL.

OR

(b) Expand the term PPP. What is the use of PPP?

SECTION – C (3×3=9)

29. Write a Python function that displays all the lines containing the word ‘ vote’ from a text file “Electronics.txt”. For example if the file contains:
In an election many people vote to choose the representative.
The candidate getting the maximum share of votes stands elected.
Normally, one person has to vote once.
The process of voting may vary with time and reason.
Then the output should be:
In an election many people vote to choose their representative.
Normally, one person has to vote once.

OR

Write a Python function that displays all the words starting and ending with a vowel from a text file “Report.txt”. The consecutive words should be separated by a space in the output. For example, if the file contains:
Once there was a wise man in a village.
He was an awesome story-teller.
He was able to keep people anchored while listening to him.
Then the output should be:
Once a a awesome able

30. A stack, named ClrStack, contains records of some colors. Each record is represented as a tuple containing four elements – ColorName, RED, GREEN, BLUE. ColorName is a string, and RED, GREEN, BLUE are integers. For example, a record in the stack may be ('Yellow', 237, 250, 68)
Write the following user-defined functions in Python to perform the specified operations on ClrStack:

(i) pus_Clr(ClrStack, new_Clr): This function takes the stack ClrStack and a new record new_Clr as arguments and pushes this new record on to the stack.

(ii) pop_Clr(ClrStack): This function pops the top most record from the stack and returns it. If the stack is already empty, the function should display the message “Underflow”.

(iii) isEmpty(ClrStack): This function checks whether the stack is empty. If the stack is empty, the function should return True, otherwise the function should return False.

OR

(b) Write the following user-defined functions in Python:

(i) push_trail (N, myStack): Here N and mystack are lists, and myStack represents a stack. The function should push the last 5 elements from the list N onto the stack myStack. For example, if the list N is [1,2,3,4,5,6,7], then the function push_trail() should push the elements 3,4,5,6,7 onto the stack. Therefore the value of stack will be [3,4,5,6,7].
Assume that N contains at least 5 elements.

(ii) pop_one (myStack): The function should pop an element from the stack myStack, and return this element. If the stack is empty, then the function should display the message 'Stack Underflow', and return None.

(iii) display_all (myStack): The function should display all the elements of the stack myStack, without deleting them. If the stack is empty, the function should display the message 'Empty Stack'.

31. Predict the output of the following code:

def ExamOn (mystr):
	newstr = ""
	count = 0
	for i in mystr:
		if count%2!=0:
			newstr = newstr + str(count-1)
		else:
			newstr = newstr + i.lower()
		count += 1
	newstr = newstr + mystr[:2]
	print("The new string is:", newstr)
ExamOn ("GenX")

OR

(b) Write the output on execution of the following Python code:

def Change (X):
	for K,V in X.items():
	L1.append(K)
	L2.append (V)
D=(1:"ONE",2: "TWO", 3: "THREE"}
L1=[]
L2=[]
Change (D)
print (L1)
print (L2)
print (D)

SECTION- D (4×4=16)

32. Suman has created a table named WORKER with a set of records to maintain the data of the construction sites, which consists of WID, WNAME, WAGE, HOURS, TYPE, and SITEID. After creating the table, she entered data in it, which is as follows:

WID	WNAME	WAGE	HOURS	TYPE	SITEID
W01	Ahmed J	1500	200	Unskilled	103
W11	Naveen S	520	100	Skilled	101
W02	Jacob B	780	95	Unskilled	101
W15	Nihal K	560	110	Semiskilled	NULL
W10	Anju S	1200	130	Skilled	103

(a) Based on the data given above, answer the following questions:
(i) Write the SQL statement to display the names and wages of those workers whose wages are between 800 and 1500.
(ii) Write the SQL statement to display the record of workers whose SITEID is not known.
(iii) Write the SQL statement to display WNAME, WAGE and HOURS of all those workers whose TYPE is ‘Skilled’.
(iv) Write the SQL statement to change the WAGE to 1200 of the workers where the TYPE is “Semiskilled”.

OR

(b) Considering the above given table WORKER, write the output on execution of the following SQL commands:
(i) SELECT WNAME, WAGE HOURS FROM WORKER WHERE SITEID = 103;
(ii) SELECT COUNT (DISTINCT TYPE) FROM WORKER;
(iii) SELECT MAX(WAGE), MIN (WAGE), TYPE FROM WORKER GROUP BY TYPE;
(iv) SELECT WNAME, SITEID FROM WORKER WHERE TYPE=”Unskilled” ORDER BY HOURS;

33. A csv file "P_record.csv" contains the records of patients in a hospital. Each record of the file contains the following data:

• Name of a patient
• Disease
• Number of days patient is admitted
• Amount

For example, a sample record of the file may be:
[“Gunjan”, “Jaundice”, 4,15000]
Write the following Python functions to perform the specified operations on this file:
(i) Write a function read_data() which reads all the data from the file and displays the details of all the ‘Cancer’ patients.
(ii) Write a function count_rec() which counts and returns the number of records in the file.

34. Assume that you are working in the IT Department of a Creative Art Gallery (CAG), which sells different forms of art creations like Paintings, Sculptures etc. The data of Art Creations and Artists are kept in tables Articles and Artists respectively. Following are few records from these two tables:

Table: Articles

Code	A_Code	Article	DOC	Price
PL001 SC028 QL005	A0001 A0004 A0003	Painting Sculpture Quilling	2018-10-19 2021-01-15 2024-04-24	20000 16000 3000

Table: Artists

A_Code	Name	Phone	Email	DOB
A0001 A0002 A0003 A0004	Roy Ghosh Gargi Mustafa	595923 1122334 121212 33333333	r@CrAG.com ghosh@CrAG.com Gargi@CrAG.com Mf@CrAG.com	1986-10-12 1972-02-05 1996-03-22 2000-01-01

As an employee of CAG, you are required to write the SQL queries for the following:
(i) To display all the records from the Articles table in descending order of price.
(ii) To display the details of Articles which were created in the year 2020.
(iii) To display the structure of Artists table.
(iv) (a) To display the name of all artists whose Article is Painting through Equi Join.
OR
(b) To display the name of all Artists whose Article is ‘Painting’ through Natural Join.

35. A table, named THEATRE, in CINEMA fatabase, has the following structure:

Field	Type
Th_ID Name City Location Seats	char(5) varchar(15) varchar(15) varchar(15) int

SECTION- E (2×5=10)

36. A file, PASSENGERS.DAT, stores the records of passengers using the following structure:
[PNR, PName, BRDSTN, DESTN, FARE]
where:
PNR – Passenger Number (string type)
PName – Passenger Name (string type)
BRDSTN – Boarding Station Name (string type)
DESTN – Destination Station Name (string type)
FARE – Fare amount for the journey (float type)
Write user defined functions in Python for the following tasks:
(i) Create() – to input data for passengers and write it in the binary file PASSENGERS.DAT.
(ii) SearchDestn (D) – to read contents from the file PASSENGERS.DAT and display the details of those Passengers whose DESTN matches with the value of D.
(iii) UpdateFare () – to increase the fare of all passengers by 5% and rewrite the updated records into the file PASSENGERS.DAT.

37. Swabhaav’ is a big NGO working in the field of Psychological Treatment and Counselling, having its Head Office in Nagpur. It is planning to set up a center in Vijayawada. The Vijayawada Center will have four blocks ADMIN, PSYCHIATRY, PSYCHOLOGY, and ICU. You, as a Network Expert, need to suggest the best network-related solutions for them to resolve the issues/problems mentioned in questions (i) to (v), keeping the following parameters in mind :

Block to Block distance (in metres):

From	To	Distance
ADMIN	PSYCHIATRY	65 m
ADMIN	PSYCHIATRY	65 m
ADMIN	ICU	65 m
PSYCHIATRY	PSYCHIATRY	100 m
PSYCHIATRY	ICU	50 m
PSYCHIATRY	ICU	50 m

Number of Computers in each block is as follows:

Block	No. of Computers
ADMIN	16
PSYCHIATRY	40
PSYCHIATRY	19
ICU	20

(i) Suggest the most appropriate location of the server inside the Vijayawada Center. Justify your choice.
(ii) Which hardware device will you suggest to connect all the computers within each block of Vijayawada Center?
(iii) Draw a cable layout to efficiently connect various blocks within the Vijayawada Center.
(iv) Where should the router be placed to provide internet to all the computers in the Vijayawada Center?
(a) The Manager at Nagpur wants to remotely access the computer in Admin block in Vijayawada. Which protocol will be used for this?
OR
(b) Which type of Network (PAN, LAN, MAN or WAN) will be set up among the computers connected with Vijayawada Center?