Computer Science - Class XII
Solved Sample Paper 2022-23

Maximum Marks: 70
Time Allowed: 3 hours

SECTION - A

Question 1. State True or False –
“Variable declaration is implicit in Python.”

Question 2. Which of the following is an invalid datatype in Python?

  1. Set
  2. None
  3. Integer
  4. Real

Question 3. Given the following dictionaries

dict_exam={"Exam":"AISSCE", "Year":2023}
dict_result={"Total":500, "Pass_Marks":165}

Which statement will merge the contents of both dictionaries?

  1. dict_exam.update(dict_result)
  2. dict_exam + dict_result
  3. dict_exam.add(dict_result)
  4. dict_exam.merge(dict_result)

Question 4. Consider the given expression:
not True and False or True
Which of the following will be correct output if the given expression is evaluated?

  1. True
  2. False
  3. NONE
  4. NULL

Question 5. 

Select the correct output of the code:
  a = "Year 2022 at All the best"
  a = a.split('2')
  b = a[0] + ". " + a[1] + ". " + a[3]
  print (b)
  1. Year . 0. at All the best
  2. Year 0. at All the best
  3. Year . 022. at All the best
  4. Year . 0. at all the best

Question 6. Which of the following mode in file opening statement results or generates an error if the file does not exist?

  1. a+
  2. r+
  3. None of the above

Question 7. Fill in the blank:
______ command is used to remove primary key from a table in SQL.

  1. update
  2. remove
  3. alter
  4. drop

Question 8. Which of the following commands will delete the table from MYSQL database?

  1. DELETE TABLE
  2. DROP TABLE
  3. REMOVE TABLE
  4. ALTER TABLE

Question 9. Which of the following statement(s) would give an error after executing the following code?

  S="Welcome to class XII"     # Statement 1
  print(S)                     # Statement 2
  S="Thank you"                # Statement 3
  S[0]= '@'                    # Statement 4
  S=S+"Thank you"              # Statement 5
  1. Statement 3
  2. Statement 4
  3. Statement 5
  4. Statement 4 and 5

Question 10. Fill in the blank:
_________ is a non-key attribute, whose values are derived from the primary key of some other table.

  1. Primary Key
  2. Foreign Key
  3. Candidate Key
  4. Alternate Key

Question 11. The correct syntax of seek() is:

  1. file_object.seek(offset [, reference_point])
  2. seek(offset [, reference_point])
  3. seek(offset, file_object)
  4. seek.file_object(offset)

Question 12. Fill in the blank:
The SELECT statement when combined with __________ clause, returns records without repetition.

  1. DESCRIBE
  2. UNIQUE
  3. DISTINCT
  4. NULL

Question 13. Fill in the blank:
______is a communication methodology designed to deliver both voice and multimedia communications over Internet protocol.

  1. VoIP
  2. SMTP
  3. PPP
  4. HTTP

Question 14. What will the following expression be evaluated to in Python?
print(15.0 / 4 + (8 + 3.0))

  1. 14.75
  2. 14.0
  3. 15
  4. 15.5

Question 15. Which function is used to display the total number of records from a table in a database?

  1. sum(*)
  2. total(*)
  3. count(*)
  4. return(*)

Question 16. To establish a connection between Python and SQL database, connect() is used. Which of the following arguments may not necessarily be given while calling connect() ?

  1. host
  2. database
  3. user
  4. password

Questions 17 and 18 are ASSERTION AND REASONING based questions. Mark the correct choice as

  1. Both A and R are true and R is the correct explanation for A
  2. Both A and R are true and R is not the correct explanation for A
  3. A is True but R is False
  4. A is false but R is True

Question 17. Assertion (A):- If the arguments in a function call statement match the number and order of arguments as defined in the function definition, such arguments are called positional arguments.

>Reasoning (R):- During a function call, the argument list first contains default argument(s) followed by positional argument(s).

Question 18. Assertion (A): CSV (Comma Separated Values) is a file format for data storage which looks like a text file.

Reason (R): The information is organized with one record on each line and each field is separated by comma.

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SECTION - B

Question 19. Rao has written a code to input a number and check whether it is prime or not. His code is having errors. Rewrite the correct code and underline the corrections made.

   
  def prime():
  n=int(input("Enter number to check :: ")
  for i in range (2, n//2):
      if n%i=0:
          print("Number is not prime \n")
      break
      else:
          print("Number is prime \n")

Question 20. Write two points of difference between Circuit Switching and Packet Switching.

OR

Write two points of difference between XML and HTML.

Question 21. (a) Given is a Python string declaration:
myexam="@@CBSE Examination 2022@@"
Write the output of: print(myexam[::-2])

(b) Write the output of the code given below:

my_dict = {"name": "Aman", "age": 26}
my_dict['age'] = 27
my_dict['address'] = "Delhi"
print(my_dict.items())

Question 22. Explain the use of 'Foreign Key' in a Relational Database Management System. Give example to support your answer.

Question 23. (a) Write the full forms of the following:

  1. SMTP
  2. PPP

(b) What is the use of TELNET?

Question 24. Predict the output of the Python code given below:

def Diff(N1,N2):
    if N1>N2:
        return N1-N2
    else:
        return N2-N1
NUM= [10,23,14,54,32]
for CNT in range (4,0,-1):
    A=NUM[CNT]
    B=NUM[CNT-1]
    print(Diff(A,B),'#', end=' ')

OR

Predict the output of the Python code given below:

tuple1 = (11, 22, 33, 44, 55 ,66)
list1 =list(tuple1)
new_list = []
for i in list1:
    if i%2==0:
        new_list.append(i)
new_tuple = tuple(new_list)
print(new_tuple)

Question 25. Differentiate between COUNT() and COUNT(*) functions in SQL with appropriate example.

OR

Categorize the following commands as DDL or DML:
INSERT, UPDATE, ALTER, DROP

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SECTION - C

Question 26 (a) Consider the following tables – Bank_Account and Branch:

Table: Bank_Account

ACode Name Type
A01 Amrita Savings
A02 Parthodas Current
A03 Miraben Current


Table: Branch

ACode City
A01 Delhi
A02 Mumbai
A01 Nagpur

What will be the output of the following statement?
SELECT * FROM Bank_Account NATURAL JOIN Branch;

(b) Write the output of the queries (i) to (iv) based on the table, TECH_COURSE given below:

Table: TECH_COURSE

CID CNAME FEES STARTDATE TID
C201 Animation and VFX 12000 2022-07-02 101
C202 CADD 15000 2021-11-15 NULL
C203 DCA 10000 2020-10-01 102
C204 DDTP 9000 2021-09-15 104
C205 Mobile Application Development 18000 2022-11-01 101
C206 Digital marketing 16000 2022-07-25 103

(i) SELECT DISTINCT TID FROM TECH_COURSE;

(ii) SELECT TID, COUNT(*), MIN(FEES) FROM TECH_COURSE GROUP BY TID HAVING COUNT(TID)>1;

(iii) SELECT CNAME FROM TECH_COURSE WHERE FEES>15000 ORDER BY CNAME;

(iv) SELECT AVG(FEES) FROM TECH_COURSE WHERE FEES BETWEEN 15000 AND 17000;

Question 27. Write a method COUNTLINES() in Python to read lines from text file 'TESTFILE.TXT' and display the lines which are not starting with any vowel.

Example:
If the file content is as follows:
An apple a day keeps the doctor away.
We all pray for everyone's safety.
A marked difference will come in our country.
The COUNTLINES() function should display the output as:
The number of lines not starting with any vowel - 1

OR

Write a function ETCount() in Python, which should read each character of a text file “TESTFILE.TXT” and then count and display the count of occurrence of alphabets E and T individually (including small cases e and t too). Example:
If the file content is as follows:
Today is a pleasant day.
It might rain today.
It is mentioned on weather sites
The ETCount() function should display the output as:
The number of E or e: 6
The number of T or t : 9

Question 28. (a) Write the outputs of the SQL queries (i) to (iii) based on the relations Teacher and Placement given below:

Table : Teacher

T_ID Name Age Department Date_of_join Salary Gender
1 Arunan 34 Computer Sc 2019-01-10 12000 M
2 Saman 31 History 2017-03-24 20000 F
3 Randeep 32 Mathematics 2020-12-12 30000 M
4 Samira 35 History 2018-07-01 40000 F
5 Raman 42 Mathematics 2021-09-05 25000 M
6 Shyam 50 History 2019-06-27 30000 M
7 Shiv 44 Computer Sc 2019-02-25 21000 M
8 Shalakha 33 Mathematics 2018-07-31 20000 F

Table : Placement

P_ID Department Place
 1 History Ahmedabad
2 Mathematics  Jaipur
3  Computer Sc Nagpur

(i) SELECT Department, avg(salary) FROM Teacher GROUP BY Department;

(ii) SELECT MAX(Date_of_Join),MIN(Date_of_Join) FROM Teacher;

(iii)SELECT Name, Salary, T.Department, Place FROM Teacher T, Placement P WHERE T.Department = P.Department AND Salary>20000;

(iv)SELECT Name, Place FROM Teacher T, Placement P WHERE Gender='F' and T.Department=P.Department;

(b) Write the command to view all tables in a database.

Question 29. Write a function INDEX_LIST(L), where L is the list of elements passed as argument to the function. The function returns another list named indexList that stores the indices of all Non-Zero Elements of L.

For example:
If L contains [12,4,0,11,0,56]
The indexList will have - [0,1,3,5]

Question 30. A list contains following record of a customer:
[Customer_name, Phone_number, City]

Write the following user defined functions to perform given operations on the stack named status:
(i) Push_element() - To Push an object containing name and Phone number of customers who live in Goa to the stack
(ii) Pop_element() - To Pop the objects from the stack and display them. Also, display "Stack Empty" when there are no elements in the stack.

For example:
If the lists of customer details are:
["Gurdas", "99999999999","Goa"]
["Julee", "8888888888","Mumbai"]
["Murugan","77777777777","Cochin"]
["Ashmit", "1010101010","Goa"]

The stack should contain
["Ashmit","1010101010"]
["Gurdas","9999999999"]

The output should be:
["Ashmit","1010101010"]
["Gurdas","9999999999"]
Stack Empty

OR

Write a function in Python, Push(SItem) where , SItem is a dictionary containing the details of stationary items– {Sname:price}. The function should push the names of those items in the stack who have price greater than 75. Also display the count of elements pushed into the stack.
For example:
If the dictionary contains the following data:
Ditem={"Pen":106,"Pencil":59,"Notebook":80,"Eraser":25}

The stack should contain
Notebook
Pen

The output should be:
The count of elements in the stack is 2

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SECTION - D

Question 31. MakeInIndia Corporation, an Uttarakhand based IT Training company, is planning to set up training centres in various cities in next 2 years. Their first campus is coming up in Kashipur district. At Kashipur campus, they are planning to have 3 different blocks for App development, Web designing and Movie Editing. Each block has number of computers, which are required to be connected in a network for communication, data and resource sharing. As a network consultant of this company, you have to suggest the best network related solutions for them for issues/problems raised in question nos. (i) to (v), keeping in mind the distances between various blocks/locations and other given parameters.

Distance between various blocks/locations:

Block Distance
App development to Web designing 28 m
App development to Movie editing 55 m
Web designing to Movie editing 32 m
Kashipur Campus to Mussoorie Campus 232 km

Number of computers

Block Number of Computers
App development 75
Web designing 50
Movie editing 80

(i) Suggest the most appropriate block/location to house the SERVER in the Kashipur campus (out of the 3 blocks) to get the best and effective connectivity. Justify your answer.

(ii) Suggest a device/software to be installed in the Kashipur Campus to take care of data security.

(iii) Suggest the best wired medium and draw the cable layout (Block to Block) to economically connect various blocks within the Kashipur Campus.

(iv) Suggest the placement of the following devices with appropriate reasons:
a. Switch / Hub
b. Repeater

(v) Suggest the protocol that shall be needed to provide Video Conferencing solution between Kashipur Campus and Mussoorie Campus.

Question 32.(a) Write the output of the code given below

    p=5
    def sum(q,r=2):
        global p
        p=r+q**2
        print(p, end= '#')
    
    a=10
    b=5    
    sum(a,b)
    sum(r=5,q=1)

(b) The code given below reads the following record from the table named student and displays only those records who have marks greater than 75:

Note the following to establish connectivity between Python and MYSQL:

RollNo – integer
Name – string
Clas – integer
Marks – integer
Note the following to establish connectivity between Python and MYSQL:

  • Username is root
  • Password is tiger

The table exists in a MYSQL database named school.

Write the following missing statements to complete the code:
Statement 1 - to form the cursor object
Statement 2 - to execute the query that extracts records of those students whose marks are greater than 75.
Statement 3 - to read the complete result of the query (records whose marks are greater than 75) into the object named data, from the table student in the database.

import mysql.connector as mysql
def sql_data():
    con1=mysql.connect(host="localhost",user="root",password="tiger", database="school")
    mycursor=_______________ #Statement 1
    print("Students with marks greater than 75 are : ")
    _________________________ #Statement 2
    data=__________________ #Statement 3
    for i in data:
        print(i)
    print()

Question 33. What is the advantage of using a csv file for permanent storage? Write a Program in Python that defines and calls the following user defined functions:

(a) ADD() – To accept and add data of an employee to a CSV file 'record.csv'. Each record consists of a list with field elements as empid, name and mobile to store employee id, employee name and employee salary respectively.

(b) COUNTR() – To count the number of records present in the CSV file named 'record.csv'.

OR

Give any one point of difference between a binary file and a csv file. Write a Program in Python that defines and calls the following user defined functions:

(a) add() – To accept and add data of an employee to a CSV file 'furdata.csv'. Each record consists of a list with field elements as fid, fname and fprice to store furniture id, furniture name and furniture price respectively.

(b) search()- To display the records of the furniture whose price is more than 10000.

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SECTION - E

Question 34. Navdeep creates a table RESULT with a set of records to maintain the marks secured by students in Sem 1, Sem2, Sem3 and their division. After creation of the table, he has entered data of 7 students in the table.

Table: RESULT

ROLL_No SNAME SEM1 SEM2 SEM3 DIVISION
101 KARAN 366 410 402 I
102 NAMAN 300 350 325 I
103 ISHA 400 410 415 I
104 RENU 350 357 415 I
105 ARPIT 100 75 178 IV
106 SABINA 100 205 217 II
107 NEELAM 470 450 471 I

Based on the data given above answer the following questions:

  1. Identify the most appropriate column, which can be considered as Primary key.
  2. If two columns are added and 2 rows are deleted from the table result, what will be the new degree and cardinality of the above table?
  3. Write the statements to:
    (a) Insert the following record into the table
    Roll No- 108, NameAadit, Sem1- 470, Sem2-444, Sem3-475, Div – I.
    (b) Increase the SEM2 marks of the students by 3% whose name begins with 'N'.

OR (Option for Part iii only)

Write the statements to:
a. Delete the record of students securing IV division.
b. Add a column REMARKS in the table with datatype as varchar with 50 characters

Question 35. Aman is a Python programmer. He has written a code and created a binary file record.dat with employeeid, ename and salary. The file contains 10 records.

He now has to update a record based on the employee id entered by the user and update the salary. The updated record is then to be written in the file temp.dat. The records which are not to be updated also have to be written to the file temp.dat. If the employee id is not found, an appropriate message should to be displayed.

As a Python expert, help him to complete the following code based on the requirement given above: 

    import _______                                  #Statement 1
    def update_data():
       rec={}
       fin=open("record.dat","rb")
       fout=open("_____________")                  #Statement 2
       found=False
       eid=int(input("Enter employee id to update their salary :: "))
       while True:
           try:
               rec=______________                  #Statement 3
               if rec["Employee id"]==eid:
                   found=True 
           rec["Salary"]=int(input("Enter new salary ::"))
           pickle.____________ #Statement 4
           else:
               pickle.dump(rec,fout)
           except:
           break
       if found==True:
           print("The salary of employee id ",eid," has been updated.")
       else:
           print("No employee with such id is not found")
    fin.close()
    fout.close()
  1. Which module should be imported in the program? (Statement 1)
  2. Write the correct statement required to open a temporary file named temp.dat for writing the updated data. (Statement 2)
  3. Which statement should Aman fill in Statement 3 to read the data from the binary file, record.dat and in Statement 4 to write the updated data in the file, temp.dat?