CBSE Class 12 Computer Science (083) 2024 Paper

Question 1

State True or False : While defining a function in Python, the positional parameters in the function header must always be written after the default parameters.

Accepted Answer

False

Question 2

The SELECT statement when combined with _____ clause, returns records without repetition.

Accepted Answer

(a) DISTINCT

Question 3

What will be the output of the following statement : print (16*5/4*2/5-8)

Accepted Answer

(c) 0.0

Question 4

What possible output from the given options is expected to be displayed when the following Python code is executed ? [code]

Accepted Answer

(a) YELLOW # RED #

Question 5

In SQL, the aggregate function which will display the cardinality of the table is ______ .

Accepted Answer

(b) count(*)

Question 6

Which protocol out of the following is used to send and receive emails over a computer network ?

Accepted Answer

(d) SMTP

Question 7

Identify the invalid Python statement from the following :

Accepted Answer

(d) g = dict{}

Question 8

Consider the statements given below and then choose the correct output from the given options : [code]

Accepted Answer

(b) MISS#SIPPI

Question 9

Identify the statement from the following which will raise an error :

Accepted Answer

(c) print("15" + 3)

Question 10

Select the correct output of the following code : [code]

Accepted Answer

(b) ['Presidency@2023']

Question 11

Which of the following options is the correct unit of measurement for network bandwidth ?

Accepted Answer

(c) Hz

Question 12

Observe the given Python code carefully : [code] Select the correct output from the given options :

Accepted Answer

(b) 20

Question 13

State whether the following statement is True or False : While handling exceptions in Python, name of the exception has to be compulsorily added with except clause.

Accepted Answer

False

Question 14

Which of the following is not a DDL command in SQL ?

Accepted Answer

(c) UPDATE

Question 15

Fill in the blank : ________ is a set of rules that needs to be followed by the communicating parties in order to have a successful and reliable data communication over a network.

Accepted Answer

Protocol

Question 16

Consider the following Python statement : F=open('CONTENT.TXT') Which of the following is an invalid statement in Python ?

Accepted Answer

(c) F.seek(0,-1)

Question 17

Assertion (A) : CSV file is a human readable text file where each line has a number of fields, separated by comma or some other delimiter. Reason (R) : writerow() method is used to write a single row in a CSV file.

Accepted Answer

(b) Both (A) and (R) are true and (R) is not the correct explanation for (A).

Question 18

Assertion (A) : The expression "Hello".sort() in Python will give an error. Reason (R) : sort() does not exist as a method/function for strings in Python.

Accepted Answer

(a) Both (A) and (R) are true and (R) is the correct explanation for (A).

Question 19

Expand the following terms : XML ,PPP

Accepted Answer

XML: eXtensible Markup Language
PPP: Point-to-Point Protocol

Question 20

Give one difference between circuit switching and packet switching.

Accepted Answer

Circuit Switching establishes a dedicated path; Packet Switching splits data into packets sent independently.

Question 21

Define the term web hosting.

Accepted Answer

Web hosting is a service that allows organizations and individuals to post a website or web page onto the Internet.

Question 22

Name any two web browsers.

Accepted Answer

Google Chrome, Mozilla Firefox

Question 23

The code given below accepts five numbers and displays whether they are even or odd : Observe the following code carefully and rewrite it after removing all syntax and logical errors : Underline all the corrections made. [code]

Accepted Answer

```python
def EvenOdd():                            # Error 1: added colon
    for i in range(5):
        num = int(input("Enter a number"))  # Error 2: closed parenthesis
        if num % 2 == 0:                     # Error 3: / changed to %
            print("Even")
        else:
            print("Odd")                     # Error 4: indented under else
EvenOdd()
```

Question 24

Write a user defined function in Python named Puzzle(W,N) which takes the argument W as an English word and N as an integer and returns the string where every Nth alphabet of the word W is replaced with an underscore ("_").

For example : if W contains the word "TELEVISION" and N is 3, then the function should return the string "TE_EV_SI_N". Likewise for the word "TELEVISION" if N is 4, then the function should return "TEL_VIS_ON".

Accepted Answer

```python
def showGrades(S):
    for K, V in S.items():
        if sum(V)/3 >= 90:
            Grade = "A"
        elif sum(V)/3 >= 60:
            Grade = "B"
        else:
            Grade = "C"
        print(K, "-", Grade)
```

Question 25

Write a user defined function in Python named Puzzle(W,N) which takes the argument W as an English word and N as an integer and returns the string where every Nth alphabet of the word W is replaced with an underscore ("_").

For example : if W contains the word "TELEVISION" and N is 3, then the function should return the string "TE_EV_SI_N". Likewise for the word "TELEVISION" if N is 4, then the function should return "TEL_VIS_ON".

Accepted Answer

```python
def Puzzle(W, N):
    NewW = ""
    for i in range(len(W)):
        if (i + 1) % N == 0:
            NewW += "_"
        else:
            NewW += W[i]
    return NewW

print(Puzzle("TELEVISION", 3))
```

Question 26

Write the output displayed on execution of the following Python code : [code]

Accepted Answer

```text
HIMALAYA#8
ALPS#4
```

Question 27

(ii) To display the number of occurrences of the substring "is" in a string named message. For example, if the string message contains "This is his book", then the output will be 3.

Accepted Answer

```python
print(message.count("is"))
```

Question 28

Ms. Veda created a table named Sports in a MySQL database, containing columns Game_id, P_Age and G_name. After creating the table, she realized that the attribute, Category has to be added. Help her to write a command to add the Category column. Thereafter, write the command to insert the following record in the table:

Game_id : G42 P_Age : Above 18 G_name : Chess Category : Senior

Accepted Answer

ALTER TABLE Sports ADD Category VARCHAR(20);
INSERT INTO Sports VALUES('G42', 'Above 18', 'Chess', 'Senior');

Question 29

Write the SQL commands to perform the following tasks: (i) View the list of tables in the database, Exam.

Accepted Answer

SHOW TABLES;

Question 30

(ii) View the structure of the table, Term1.

Accepted Answer

DESCRIBE Term1;

Question 31

Predict the output of the following code : [code]

Accepted Answer

```text
300 # 100
300 @ 200
210 # 200
300 @ 210
```

Question 32

Write the Python statement for each of the following tasks using built-in functions/methods only :

(i) To remove the item whose key is "NISHA" from a dictionary named Students. For example, if the dictionary Students contains {"ANITA":90, "NISHA":76, "ASHA":92}, then after removal the dictionary should contain {"ANITA":90, "ASHA":92}.

Accepted Answer

```python
Students.pop("NISHA")
# OR
del Students["NISHA"]
```

Question 33

A tuple named subject stores the names of different subjects. Write the Python commands to convert the given tuple to a list and thereafter delete the last element of the list.

Accepted Answer

```python
subject = list(subject)
subject.pop()
# OR
subject = list(subject)
del subject[-1]
```

Question 34

Write the output on execution of the following Python code : [code]

Accepted Answer

```text
R*A*C*E*C*A*R*
C#a#r#
R*A*D*A*R*
```

Question 35

Consider the table ORDERS given below and write the output of the SQL queries that follow : |ORDNO|ITEM|QTY|RATE|ORDATE| |---|---|---|---|---| |1001|RICE|23|120|2023-09-10| |1002|PULSES|13|120|2023-10-18| |1003|RICE|25|110|2023-11-17| |1004|WHEAT|28|65|2023-12-25| |1005|PULSES|16|110|2024-01-15| |10

Accepted Answer

(i)
|ITEM|SUM(QTY)|
|---|---|
|RICE|48|
|PULSES|29|
|WHEAT|80|

(ii)
|ITEM|QTY|
|---|---|
|RICE|25|
|WHEAT|28|

(iii)
|ORDNO|ORDATE|
|---|---|
|1004|2023-12-25|
|1007|2024-04-30|

Question 36

Write a user defined function in Python named Puzzle(W,N) which takes the argument W as an English word and N as an integer and returns the string where every Nth alphabet of the word W is replaced with an underscore ("_").

For example : if W contains the word "TELEVISION" and N is 3, then the function should return the string "TE_EV_SI_N". Likewise for the word "TELEVISION" if N is 4, then the function should return "TEL_VIS_ON".

Accepted Answer

```python
def showInLines():
    with open("STORY.TXT", 'r') as F:
        content = F.read()
    sentence = ""
    for ch in content:
        sentence += ch
        if ch in "." + "?" + "!":
            print(sentence)
            sentence = ""
    if sentence:
        print(sentence)
```

Question 37

Write a function, c_words() in Python that separately counts and displays the number of uppercase and lowercase alphabets in a text file, Words.txt.

Accepted Answer

```python
def c_words():
    f = open("Words.txt", "r")
    Txt = f.read()
    CUpper = 0
    CLower = 0
    for ch in Txt:
        if ch.isupper():
            CUpper += 1
        elif ch.islower():
            CLower += 1
    print("Uppercase:", CUpper, "Lowercase:", CLower)
    f.close()
```

Question 38

Consider the table Projects given below : Table : Projects |P_id|Pname|Language|Startdate|Enddate| |---|---|---|---|---| |P001|School Management System|Python|2023-01-12|2023-04-03| |P002|Hotel Management System|C++|2022-12-01|2023-02-02| |P003|Blood Bank|Python|2023-02-11|2023-03-02| |P004|Payroll

Accepted Answer

(i) ALTER TABLE Projects ADD PRIMARY KEY (P_id);

(ii) UPDATE Projects SET Language='Python' WHERE P_id='P002';

(iii) DROP TABLE Projects;

Question 39

Consider a list named Nums which contains random integers. Write the following user defined functions in Python and perform the specified operations on a stack named BigNums. (i) PushBig() : It checks every number from the list Nums and pushes all such numbers which have 5 or more digits into the st

Accepted Answer

```python
def PushBig(Nums, BigNums):
    for N in Nums:
        if len(str(N)) >= 5:
            BigNums.append(N)

def PopBig(BigNums):
    while BigNums:
        print(BigNums.pop())
    print("Stack Empty")
```

Question 40

Consider the tables Admin and Transport given below : Table : Admin |S_id|S_name|Address|S_type| |---|---|---|---| |S001|Sandhya|Rohini|Day Boarder| |S002|Vedanshi|Rohtak|Day Scholar| |S003|Vibhu|Raj Nagar|NULL| |S004|Atharva|Rampur|Day Boarder| Table : Transport |S_id|Bus_no|Stop_name| |---|---|---

Accepted Answer

(i) SELECT S_name, Stop_name FROM Admin, Transport WHERE Admin.S_id = Transport.S_id;

(ii) SELECT COUNT(*) FROM Admin WHERE S_type IS NULL;

(iii) SELECT * FROM Admin WHERE S_name LIKE 'V%';

(iv) SELECT S_id, Address FROM Admin ORDER BY S_name;

Question 41

Sangeeta is a Python programmer working in a computer hardware company. She has to maintain the records of the peripheral devices. She created a csv file named Peripheral.csv, to store the details. The structure of Peripheral.csv is: [code] where: - P_id is Peripheral device ID (integer) - P_name is

Accepted Answer

```python
import csv

def Add_Device():
    F = open("Peripheral.csv", "a", newline='')
    W = csv.writer(F)
    P_id = int(input("Enter the Peripheral ID: "))
    P_name = input("Enter Peripheral Name: ")
    Price = int(input("Enter Price: "))
    W.writerow([P_id, P_name, Price])
    F.close()

def Count_Device():
    F = open("Peripheral.csv", "r")
    L = list(csv.reader(F))
    Count = 0
    for D in L:
        if int(D[2]) < 1000:
            Count += 1
    print(Count)
    F.close()
```

Question 42

(i) Differentiate between 'w' and 'a' file modes in Python.

(ii) Consider a binary file, items.dat, containing records stored in the given format:

text

{item_id: [item_name, amount]}

Write a function, Copy_new(), that copies all records whose amount is greater than 1000 from items.dat to new_items.dat.

Accepted Answer

(i)
**'w' mode** opens a file for writing. If the file does not exist, a new file is created. If it exists, its contents are truncated and replaced. The file pointer is positioned at the beginning.

**'a' mode** opens a file for appending. If the file does not exist, a new file is created. If it exists, the contents are preserved and the file pointer is placed at the end so new data is added after existing data.

(ii)
```python
import pickle

def Copy_new():
    try:
        F1 = open("items.dat

Question 43

(i) What is the advantage of using with clause while opening a data file in Python ? Also give syntax of with clause.

(ii) A binary file, EMP.DAT has the following structure:

text

[Emp_Id, Name, Salary]

where - Emp_Id : Employee id - Name : Employee Name - Salary : Employee Salary

Write a user defined function, disp_Detail(), that would read the contents of the file EMP.DAT and display the details of those employees whose salary is below 25000.

Accepted Answer

(i)
The advantage of using the **with** clause is that any file opened using it is closed automatically once control leaves the with block — even if an exception is raised.

Syntax:
```python
with open(file_name, access_mode) as file_object:
    # operations
```

Example:
```python
with open("myfile.txt", "r+") as file_object:
    content = file_object.read()
```

(ii)
```python
import pickle

def disp_Detail():
    try:
        with open("EMP.DAT", "rb") as F:
            try:
                w

Question 44

(i) Define Cartesian Product with respect to RDBMS. (ii) Sunil wants to write a program in Python to update the quantity to 20 of the records whose item code is 111 in the table named shop in MySQL database named Keeper. The table shop in MySQL contains the following attributes: - Item_code: Item co

Accepted Answer

(i)
Cartesian Product is an operation that combines rows/tuples from two tables/relations. It results in all possible pairs of rows from both tables and is denoted by 'X'. If table A has m rows and table B has n rows, the Cartesian product has m × n rows.

(ii)
```python
import pymysql as pm

DB = pm.connect(host="localhost", user="admin",
                passwd="Shopping", database="Keeper")
MyCursor = DB.cursor()
MyCursor.execute("UPDATE shop SET Qty=20 WHERE Item_code=111")
DB.commit()
DB.clo

Question 45

Infotainment Ltd. is an event management company with its prime office located in Bengaluru. The company is planning to open its new division at three different locations in Chennai named as - Vajra, Trishula and Sudershana. You, as a networking expert need to suggest solutions to the questions in p

Accepted Answer

Star topology connecting Trishula and Sudershana to Vajra.

[img:https://i.postimg.cc/XYSBSkny/Screenshot-2026-03-22-153549.png]

Question 46

(ii) Which block in Chennai division should host the server ? Justify your answer.

Accepted Answer

Vajra can host the server, as it has the maximum number of computers (120).

Question 47

(iii) Which fast and effective wired transmission medium should be used to connect the prime office at Bengaluru with the Chennai division ?

Accepted Answer

Optical Fiber

Question 48

(iv) Which network device will be used to connect the digital devices within each location of Chennai division so that they may communicate with each other ?

Accepted Answer

Switch (or Hub / Router)

Question 49

(v) A considerable amount of data loss is noticed between the different locations of the Chennai division, which are connected in the network. Suggest a networking device that should be installed to refresh the data and reduce the data loss during transmission to and from different locations of Chen

Accepted Answer

Repeater

Question 50

(i) Give any two features of SQL. (ii) Sumit wants to write a code in Python to display all the details of the passengers from the table flight in MySQL database, Travel. The table contains the following attributes: - F_code: Flight code (String) - F_name: Name of flight (String) - Source: Departure

Accepted Answer

(i) Any two of the following:
- Full form is Structured Query Language.
- Is used to retrieve and view specific data from a table in a database.
- Is case insensitive.
- Each query in SQL ends with a semicolon (;).
- It contains DDL and DML.

(ii)
```python
import pymysql as pm

DB = pm.connect(host="localhost", user="root",
                password="airplane", database="Travel")
MyCursor = DB.cursor()
MyCursor.execute("SELECT * FROM flight")
Rec = MyCursor.fetchall()
for R in Rec:
    print(R)

Average of Eng,Math,Science	Grade
>=90	A
<90 but >=60	B
<60	C

S_id	Bus_no	Stop_name
S002	TSS10	Sarai Kale Khan
S004	TSS12	Sainik Vihar
S005	TSS10	Kamla Nagar

From - To	Distance
Vajra to Trishula	350 m
Trishula to Sudershana	415 m
Sudershana to Vajra	300 m
Bengaluru Office to Chennai	2000 km

Computer Science · 2024

Section A

Section B

Section C

Section D

Section E

ORDNO	ITEM	QTY	RATE	ORDATE
1001	RICE	23	120	2023-09-10
1002	PULSES	13	120	2023-10-18
1003	RICE	25	110	2023-11-17
1004	WHEAT	28	65	2023-12-25
1005	PULSES	16	110	2024-01-15
1006	WHEAT	27	55	2024-04-15
1007	WHEAT	25	60	2024-04-30

P_id	Pname	Language	Startdate	Enddate
P001	School Management System	Python	2023-01-12	2023-04-03
P002	Hotel Management System	C++	2022-12-01	2023-02-02
P003	Blood Bank	Python	2023-02-11	2023-03-02
P004	Payroll Management System	Python	2023-03-12	2023-06-02

S_id	S_name	Address	S_type
S001	Sandhya	Rohini	Day Boarder
S002	Vedanshi	Rohtak	Day Scholar
S003	Vibhu	Raj Nagar	NULL
S004	Atharva	Rampur	Day Boarder