Computer Science (Python) Set 4 2024-2025 Commerce (English Medium) Class 12 Question Paper Solution

State True or False:

A Python List must always contain all its elements of same data typе.

What will be the output of the following statement?

print(14%3**2*4)

16

64

20

256

Identify the correct output of the following code snippet:

game="olympic2024"
print(game.index("C"))

0

6

−1

ValueError

Which of the following is the correct identifier?

global

Break

def

with

Identify the invalid Python statement out of the following options:

print("A",10,end="*")

print("A",sep="*",10)

print("A",10,sep="*")

print("A"*10)

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

L=[‘TIC’, ‘TAC’]
print(L[::-1])

[‘CIT’, ‘CAT’]

[‘TIC’, ‘TAC’]

[‘CAT’, ‘CIT’]

[‘TAC’, ‘TIC’]

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?

is

is not

and

or

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='#')

S01#S02#

95#96#

S01,95#S02,96#

S01#95#SO2#96#

While creating a table, which constraint does not allow insertion of duplicate values in the table?

UNIQUE

DISTINCT

NOT NULL

HAVING

Consider 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)

25$$15

15$$25

25$$25

2525$$

Consider 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')

ERROR#

WORD5#OVER

WORD5#

ERROR#OVER

Which of the following built-in function/method returns a dictionary?

dict()

keys()

values()

items()

Which of the following is a DML command in SQL?

UPDATE

CREATE

ALTER

DROР

Which aggregate function in SQL displays the number of values in the specified column ignoring the NULL values?

len()

count()

number()

num()

DATE

VARCHAR

FLOAТ

CHAR

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.

Which of the following networking devices is used to regenerate and transmit the weakened signal ahead?

Hub

Ethernet Card

Repeater

Modem

Which of the following options is the correct protocol used for phone calls over the internet?

PPP

FTP

HTTP

VoIP

Expand the following:

ARPANET

Assertion (A): For a binary file opened using ‘rb’ mode, the pickle.dump() method will display an error.

Reason (R): The pickle.dump() method is used to read from a binary file.

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

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

Assertion (A) is true but, Reason (R) is false.

Assertion (A) is false but, Reason (R) is true.

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.

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

Write one example of the following in Python:

Syntax Error

Write one example of the following in Python:

Implicit Type Conversion

Consider the following dictionaries, D and D1:

D={"Suman":40, "Raj":55, "Raman":60}
D1={"Aditi":30, "Amit":90, "Raj":20}

(Answer using built-in Python functions only)

Write a statement to display/return the value corresponding to the key "Raj" in the dictionary D.

Consider the following dictionaries, D and D1:

D={"Suman": 40, "Raj":55, "Raman":60}
D1={"Aditi": 30, "Amit":90, "Raj":20}

(Answer using built-in Python functions only)

Write a statement to display the length of the dictionary D1.

Consider the following dictionaries, D and D1:

D={"Suman": 40, "Raj":55, "Raman":60}
D1={"Aditi":30, "Amit":90,"Raj":20}

(Answer using built-in Python functions only)

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

Consider the following dictionaries, D and D1:

D={"Suman": 40, "Raj":55, "Raman":60}
D1={"Aditi":30, "Amit":90,"Raj":20}

(Answer using built-in Python functions only)

Write a statement to delete the item with the given key “Amit” from the dictionary D1.

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

import random
Cards=["Heart", "Spade", "Club", "Diamond"]
for i in range (2):
    print(Cards[random.randint(1,i+2) ],end="#")

Spade#Diamond#

Spade#Heart#

Diamond#Club#

Heart#Spade#

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)

Help Nisha to identify the attribute which should be designated as the PRIMARY KEY. Justify your answer. 

Help Nisha to identify the constraint which should be applied to the attribute NAME such that the Employees' Names cannot be left empty or NULL while entering the records but can have duplicate values.

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.

Write the SQL command to delete the table EMPLOYEES.

Expand the term URL.

Explain the term URL.

Expand the following term:

PPP

What is the use of PPP?

Write a Python function that displays all the lines containing the word 'vote' from a text file "Elections.txt". For example, if the file contains:

In an election many people vote to choose their representative.
The candidate getting the maximum share of votes stands elected.
Normally, one person has to vote oncе.
The process of voting may vary with time and region.
Then the output should be:
In an election many people vote to choose their representative.
Normally, one person has to vote once.

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 awesome able.

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:

1. push_Clr(ClrStack, new_Clr): This function takes the stack ClrStack and a new record new_Clr as arguments and pushes this new record onto the stack.
2. pop_Clr(ClrStack): This function pops the topmost record from the stack and returns it. If the stack is already empty, the function should display the message “Underflow".
3. 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:

Write the following user-defined functions in Python:

1. 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.
2. 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.
3. 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'.

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")

Write the output on execution of the following Python code:

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

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:

Based on the data given above, answer the following questions:

1. Write the SQL statement to display the names and wages of those workers whose wages are between 800 and 1500.
2. Write the SQL statement to display the record of workers whose SITEID is not known.
3. Write the SQL statement to display WNAME, WAGE and HOURS of all those workers whose TYPE is ‘Skilled’.
4. Write the SQL statement to change the WAGE to 1200 of the workers where the TYPE “Semiskilled”.

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:

Considering the above given table WORKER, write the output on execution of the following SQL commands:

1. SELECT WNAME, WAGE*HOURS FROM WORKER WHERE SITEID = 103;

2. SELECT COUNT (DISTINCT TYPE) FROM WORKER;

3. SELECT MAX(WAGE), MIN(WAGE), TYPE FROM WORKER GROUP BY TYРЕ;

4. SELECT WNAME, SITEID FROM WORKER WHERE TYPE="Unskilled" ORDER BY HOURS;

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:

1. Write a function read_data() which reads all the data from the file and displays the details of all the 'Cancer' patients.
2. Write a function count_rec() which counts and returns the number of records in the file.

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:

Note:

• The tables contain many more records than shown here.
• DOC is Date of Creation of an Article.

As an employee of CAG, you are required to write the SQL queries for the following:

1. To display all the records from the Articles table in descending order of price.
2. To display the details of Articles which were created in the year 2020.
3. To display the structure of Artists table.
4. 1. To display the name of all artists whose Article is Painting through Equi Join.
      OR
   2. To display the name of all Artists whose Article is 'Painting' through Natural Join.

A table, named THEATRE, in CINEMA database, has the following structure:

Write a function Delete _Theatre (), to input the value of Th_ ID from the user and permanently delete the corresponding record from the table.

Assume the following for Python-Database connectivity:

Host: localhost, User: root, Password: Ex2025

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:

1. Create()− to input data for passengers and write it in the binary file PASSENGERS.DAT.
2. 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.
3. UpdateFare()- to increase the fare of all passengers by 5% ad rewrite the updated records into the file PASSENGERS.DAT.

‘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 distances (in metres):

Distance of Nagpur Head Office from Vijayawada Center = 700 km Number of Computers in each block is as follows:

1. Suggest the most appropriate location of the server inside the Vijayawada Center. Justify your choice. 
2. Which hardware device will you suggest to connect all the computers within each block of Vijayawada Center? 
3. Draw a cable layout to efficiently connect various blocks within the Vijayawada Center. 
4. Where should the router be placed to provide internet to all the computers in the Vijayawada Center? 
5. 
   
   1. The Manager at Nagpur wants to remotely access the computer in Admin block in Vijayawada. Which protocol will be used for this?
      OR
   2. Which type of Network (PAN, LAN, MAN or WAN) will be set up among the computers connected with Vijayawada Center?