CBSE Sample Papers for Class 12 Informatics Practices Set 10 with Solutions

Students must start practicing the questions from CBSE Sample Papers for Class 12 Informatics Practices with Solutions Set 10 are designed as per the revised syllabus.

CBSE Sample Papers for Class 12 Informatics Practices Set 10 with Solutions

Time : 3 Hrs.
Max. Marks: 70

General Instructions

1. Please check this question paper contains 37 questions.
2. All questions are compulsory. However, internal choices have been provided in some questions. Attempt only one of the choices in such questions.
3. The paper is divided into 5 Sections- A, B, C, D and E.
4. Section A consists of 21 questions (1 to 21). Each question carries 1 Mark.
5. Section B consists of 7 questions (22 to 28). Each question carries 2 Marks.
6. Section C consists of 4 questions (29 to 32). Each question carries 3 Marks.
7. Section D consists of 2 case study type questions (33 to 34). Each question carries 4 Marks.
8. Section E consists of 3 questions (35 to 37). Each question carries 5 Marks.
9. All programming questions are to be answered using Python Language only.
10. In case of MCQ, text of the correct answer should also be written.

Section A

Question 1.
State whether the following statement is True and False:
A pandas Series can be sliced using index ranges similar to a Python list.
Answer:
True

Question 2.
Which of the following clause cannot be used with ALTER command?
(a) CHANGE
(b) UPDATE
(c) MODIFY
(d) ADD
Answer:
(b) UPDATE

Question 3.
A ___ is a network device that connects multiple devices together, allowing them to communicate with each other.
Answer:
(b) hub

Question 4.
The return type of POWER() function is
(a) String
(b) Date
(c) Numeric
(d) None of these
Answer:
(c) Numeric

Question 5.
______ is the filling of mailbox with unnecessary and junk mail.
(a) Phishing
(b) Spamming
(c) Spying
(d) Adware attack
Answer:
(b) Spamming

Question 6.
Which method would you use to sort a DataFrame by the values of a specific column in ascending order?
(a) sort()
(b) order()
(c) sort_values()
(d) sort_index()
Answer:
(c) sort_values()

Question 7.
Which argument must be set with plotting functions for legend() to display the legends?
(a) data
(b) label
(c) name
(d) sequence
Answer:
(b) label

Question 8.
State whether the following statement is True and False:
The SQL UPDATE statement can be used to modify existing records in a table.
Answer:
True

Question 9.
Which of the following reads data from csv files?
(a) get_csv()
(b) read_csv()
(c) csv_read()
(d) read()
Answer:
(b) read_csv

Question 10.
The ____ include right to copy (reproduce) a work, right to distribute copies of the work to the public, and right to publicly display or perform the work.
(a) Copyright
(b) Patent
(c) Create right
(d) None of these
Answer:
(a) Copyright

Question 11.
Fill in the blank:
The SQL command used to remove a table from the database is ___.
(a) DELETE
(b) REMOVE
(c) DROP TABLE
(d) TRUNCATE
Answer:
(c) DROP TABLE

Question 12.
Which of the following allows you to connect and login to a remote computer?
(a) SMTP
(b) HTTP
(c) FTP
(d) Telnet
Answer:
(d) Telnet

Question 13.
Given a Pandas Series called Sequences, the command which will display the first 4 rows is ___.
(a) print(Sequences.head (4))
(b) print(Sequences.Head (4))
(c) print(Sequences.heads(4))
(d) print(Sequences.Heads (4))
Answer:
(a) print(Sequences.head(4))

Question 14.
The digital data trail we leave online intentionally is called
(a)Active digital footprints
(b) Passive digital footprints
(c) Current digital footprints
(d) None of these
Answer:
(a) Active digital footprints

Question 15.
Given the series s1=p.Series([ 10, 20, 30, 40, 50]), >>>print(s1[0:]) shows
(a) [10, 20, 30, 40, 50]
(b) [10, 20, 30]
(c) [10]
(d) [ ]
Answer:
(a) [10, 20, 30, 40, 50]

Question 16.
Match the following SQL functions/clauses with their descriptions:

(a) P-2, Q-1, R-3, S-4
(b) P-1, Q-2, R-4, S-3
(c) P-3, Q-4, R-2, S-1
(d) P-4, Q-l, R-3, S-2
Answer:
(a) P-2, Q-1, R-3, S-4

Question 17.
In Pandas, the ____, method is used to return the number of unique elements in a DataFrame column.
(a) value_counts()
(b) unique()
(c) nunique()
(d) count()
Answer:
(c) nunique()

Question 18.
Which of the following is the attribute used to change the color of bars in a Bar Chart?
(a) colour
(b) color
(c) clr
(d) colours
Answer:
(b) color

Question 19.
What kind of transmission medium is most appropriate to carry data in a computer network that is exposed to electrical interferences?
(a) Unshielded twisted pair
(b) Optical fiber
(c) Coaxial cable
(d) Microwave
Answer:
(b) Optical fiber

Directions (Q. Nos. 20 and 21) are Assertion (A) and Reason (R) Type questions. Choose the correct option as:

(a) Both Assertion (A) and Reason (R) are true, and Reason (R) is the correct explanation of Assertion (A)
(b) Both Assertion (A) and Reason (R) are true, but Reason (R) is not the correct explanation of Assertion (A)
(c) Assertion (A) is True, but Reason (R) is False
(d) Assertion (A) is False, but Reason (R) is True

Question 20.
Assertion (A) DataFrame has both a row and column index.
Reason (R) A DataFrame is a two-dimensional labelled data structure like a table of MySQL.
Answer:
(a) Both A and R are true and R is a correct explanation of A.

Question 21.
Assertion (A) The ‘TRUNCATE’ command in SQL deletes all rows from a table.
Reason (R) The ‘TRUNCATE’ command can be rolled back using a transaction.
Answer:
(c) ‘TRUNCATE’ deletes all rows from a table, but it cannot be rolled back, as it is a DDL command. Only DELETE’ (a DML command) can be rolled back if used within a transaction. Hence A is true, but R is false.

Section B [7 × 2 = 14]

Question 22.
(A) Flow can you check for missing values in a Pandas DataFrame?
Or (B) What is the purpose of the groupby() function in Pandas? Provide an example.
Answer:
(A) You can check for missing values using the isnull() function, which returns a DataFrame of Boolean values.
Example: df.isnull()

Or

(B) The groupby() function is used to split the data into groups based on some criteria and apply a function to each group.
Example: df.groupby(’Age’).sum()

Question 23.
What is data protection? Write two steps to protect your data.
Answer:
Data protection refers to safeguarding personal and sensitive information from unauthorized access, theft, or loss.
Two steps to protect your data:

1. Use strong, unique passwords and enable two-factor authentication (2FA).
2. Regularly update software to fix security vulnerabilities and use encryption for sensitive data.

Question 24.
Consider the string: “Computer Science and Engineering”. Write suitable SQL queries for the following:
I. To extract and display “Engineering” from the string.
II. Convert the entire string to uppercase.
Answer:
I. SELECT SUBSTRING(‘Computer Science and Engineering’, 22, 11);
II. SELECT UPPER(‘Computer Science and Engineering’);

Question 25.
(A) List some benefits of networking. Name any two components required for networking.
Or
(B) Give an example of each static web page and dynamic web page.
Answer:
(A) Some of the benefits of networking are

1. File sharing
2. Hardware sharing
3. Application sharing
4. User communication
5. Access to remote database

Two components required for networking are Switch/hub and repeaters.

Or

(B) Static web page A page that contains schools or companies information. The content of this page will not change every day unless the HTML file is manually edited by a programmer who maintains it.
Dynamic web page When you login to your Yahoo E-mail account to check and to send E-mails. Moreover, the list of E-mail messages changes as it arrives or as the list is deleted or is moved to another folder.

Question 26.
What is the purpose of ORDER BY clause in SQL? Explain with the help of suitable example.
Answer:
The ORDER BY clause is used to sort the result set in ascending or descending order.
e.g. The following SQL statement displays all the customer’s names in alphabetical order.
SELECT Cname FROM Customers ORDER BY Cname:

Question 27.
Explain the concept of “intellectual property rights” (IPR).
Answer:
Intellectual property rights protect creators’ inventions and works, such as patents and copyrights. IPR ensures that creators have control over their creations and can benefit from them.

Question 28.
(A) The Python code written below has syntactical errors. Rewrite the correct code and underline the corrections made.

Import pandas as pd
Emp = {'a' : 10000. 'b' : 15000, 'c' : 12000}
Sr = Pd.Series(Emp)
Print(sr)

Or

(B) Complete the given Python code to get the required output as: 16

import ___ as np
data = [1, 4, 9, 16]
series_data = np.___(data)
print(series_data[__])

Answer:
(A) Correct code is:

import pandas as pd
Emp = {'a' : 10000, 'b' : 15000, 'c' : 12000}
sr = pd.Series(Emp)
print(sr)

Or

(B) Correct code is:

import numpy as np
data - [1, 4, 9, 16]
series_data = np.array(data)
print(series_data[3])

Section C

Question 29.
Raj has been receiving emails claiming that he has won a lottery from an unknown sender. The emails ask for personal information and bank details to claim the prize. Raj is unsure about the legitimacy of these emails but is tempted by the promise of a large sum of money.
(i) What is happening to Raj?
(ii) What immediate action should he take to handle it?
(iii) Is there any law in India to handle such issues? Discuss briefly.
Answer:
(i) Raj is being targeted by a phishing scam, where fraudulent emails are sent to trick recipients into divulging sensitive information such as personal details, passwords, or financial information.

(ii) Raj should take the following immediate actions:

• Do not respond Do not reply to the email or click on any links provided in it.
• Verify legitimacy Contact the supposed lottery organization directly through their official website or customer service number to verify if the email is genuine.
• Report Report the phishing attempt to his email service provider as spam or phishing.
• Educate others Inform friends and family about the scam to prevent them from falling victim to similar schemes.

(iii) Yes, phishing is considered a cybercrime under the Information Technology Act, 2000. Section 43, Section 66, and Section 66C of the IT Act address various aspects of cybercrimes including unauthorized access, hacking, and identity theft.

Question 30.
(A) Write a small Python code to create a DataFrame with headings (a and b) from the list given below
[[10, 20], [30, 40], [50, 60], [70, 80]]

Or

(B) Write a Python program to create the following DataFrame using a list of dictionaries.

Answer:
(A)

import pandas as pd
df1=pd.DataFrame ([[10, 20], [30, 40]], columns = ['a', 'b'])
df2=pd.DataFrame ([[50, 60], [70, 80]], columns = ['a', ‘b'])
df = df1.append (df2)
print(df)

Or

(B)

import pandas as pd
# List of dictionaries representing the data
data = [
{'A' : 21, ’B' : 12, 'C' : 69}
{'A' : 45, 'B' : 45, 'C' : 84}
{'A' : 23, 'B' : 86, ''C : 70}
{'A' : 17, 'B' : 33, 'C' : 78}
]
# Creating DataFrame
df = pd.DataFrame(data)
# Displaying the DataFrame
print(df)

Question 31.
Given the following table “Drinks” storing details of soft drinks.

Answer the following questions:
(i) If 2 rows are added to the table, what will be the degree of the table?
(ii) Can Brarnj be the Primary key of the table? Why?
(iii) Write a query to display average price of products of brand “Coca-Cola”.
Answer:
(i) Degree will be 4, It will not change as addition of rows changes the cardinality.

(ii) No, since it has duplicate values.

(iii)

SELECT AVG(Price) FROM Drinks WHERE Brand=”Coca-Cola";

Question 32.
(A) Consider the table DOCTOR given below.

Write SQL queries for the following:
(i) Display the names and salaries of doctors in descending order of salaries.
(ii) Display names of each department along with total salary being given to doctors of that department.
(iii) Display the number of doctors in each department.
Answer:
(i)

SELECT DOCName, Salary FROM DOCTOR ORDER BY Salary DESC:

(ii)

SELECT Department, SUM (Salary) FROM DOCTOR GROUP BY Department:

(iii)

SELECT Department. C0UNT(*) FROM DOCTOR GROUP BY Department:

Or

(B) Consider the following tables:

Write appropriate SQL queries for the following:
(i) Display the total number of hours worked on each project.
(ii) Display the names of all employees who have worked on more than 30 hours.
(iii) Display the employee names along with their corresponding projects.
Answer:
(i)

SELECT Project. SUM(Hours) AS Total_Hours FROM PROJECTS GROUP BY Project;

(ii)

SELECT e.Name FROM EMPLOYEE e JOIN PROJECTS p ON e.EmployeelD = p.EmployeeID WHERE p.Hours > 30:

(iii)

SELECT e.Name. p.Project FROM EMPLOYEE e JOIN PROJECTS p ON e.EmployeelD = p.EmployeelD;

Section D [2 × 4 = 8]

Question 33.
During a practical exam, a student, Ravi, has to fill in the blanks in a Python program that generates a line chart. This line chart represents the monthly sales of a store over four months.

I. Write the suitable code for the import statement in the blank space in the line marked as Statement-1.
II. Refer to the graph shown above and fill in the blank in Statement-2 with suitable Python code.
III. Fill in the blank in Statement-3 with the name of the function to set the label on the y-axis.
IV. Refer to the graph shown above and fill the blank in Statement-4 with a suitable chart title.
Answer:
I. matplotlib.pyplot
II. sales
III. plt.ylabel
IV. Monthly Sales Data

Question 34.
(A) Predict the output of the following queries

(i) Select Dname from Doctor where VisitDays IN (“Mon”,”Wed”);
(ii) Select Dept, Count(*) from Doctor Group by Dept;
(iii) Select right (Dname, 3) from Doctor where Charges >4000;
Answer:
(i) Dname
R. Sharma
D. Basak

(ii)

(iii) Right(Dname,3)
wal

Or

(B) Tejasvi Sethi, a car dealer has stored the details of all cars in her showroom in a table CARMARKET. The table CARMARKET has attributes CARCODE which is a primary key, CARNAME, COMPANY, COLOR, COST (in lakh) of the car and DOM which is the Date of Manufacture of the car.

Help her by writing answers of the following questions based on the given table.
(i) Display the camame along with the charges rounded off to 1 digit after decimal place.
(ii) Display the camame ,name of the company in lower case of all cars whose year (of dom) is 2020.
(iii) Display the number of cars manufactured each year.
(iv) Display the camame, color and position of the character ‘E’ in the color of all the cars.
Answer:
(i)

SELECT CARNAME. R0UND(C0ST, 1) FROM CARMARKET;

(ii)

SELECT CARNAME. LCASE(COMPANY) FROM CARMARKET WHERE YEAR(DOM) = 2020;

(iii)

SELECT COUNT(*) .YEAR(DOM) FROM CARMARKET GROUP BY YEAR(DOM);

(iv)

SELECT CARNAME. COLOR, INSTR(COLOR, 'E') FROM CARMARKET;

 

Section E [3 × 5 = 15]

Question 35.
Green Valley Public School has 4 buildings in its campus . Distance between the buildings and the number of computers in each is given below

(i) Which building is best suitable for placement of server?
Answer:
Building A, as it has maximum number of computers.

(ii) If building A to D is to be connected, which device will be required for strong signals?
Answer:
A repeater would be required, as signals become weak in long distances which can be amplified by a repeater.

(iii) Which building would need a switch/hub?
Answer:
Hub/switch would be required in all the buildings as they connect multiple computers.

(iv) Which topology would you suggest for connecting computers in each building?
Answer:
Star topology would be the best as it has multiple positive features.

(v) Draw cable layout to efficiently connect various buildings within the school campus for a wired connectivity.
Answer:
Cable layout

Question 36.
Consider the DataFrame df shown below.

(i) What will be the output of the following statements?

(a)

df.shape( )

(b)

df.index=[“AirIndia".“Indigo",“Spicejet”,“Jet",“Emi rates"]

Answer:
(a) (5, 3)

(b)

(ii) Write the code to get the following output:

Answer:

df[’Month', 'passengers'][df['Month']=Jan]

(iii) Predict the output of print (df[1 : 3]).
Answer:

(iv) Rename the column name ‘Passengers’ to ‘Visitors’.
Answer:

df = df.rename(columns={'Passengers': 'Visitors'})

(v) Add a column ‘Flights’ to the DataFrame df.
Answer:

flight_names = ['Spicejet', ' IndiGo'. 'Air India', 'Vistara', 'Go First']
df ['Flights'] = flight_names
print(df)

Question 37.
Write suitable SQL query for the following:

(i) To display the name of the month for the current date.
Answer:

SELECT MONTHNAME (CURDATE ()) AS MonthName:

(ii) To display the weekday name for the current date.
Answer:

SELECT DAYNAME (CURDATE ()) AS WeekdayName:

(iii) To display the position of the first occurrence of “ka” in “karnataka”.
Answer:

SELECT INSTR('karnataka', 'ka') AS Position;

(iv) To display the string in Upper case ‘Python Program’.
Answer:

SELECT UPPER!'Python Program') AS UpperCaseString;

(v) To compute the remainder of numerator 117 and denominator 17.
Answer:

SELECT MOD(117, 17) AS Remainder;

Or

Explain the following SQL functions using suitable examples.

(i) LEFT()
Answer:
LEFT() Extracts a specified number of characters from the left side of a string.

Example:

SELECT LEFT ('Hello World', 5) AS Leftstring;

(ii) INSTR()
Answer:
INSTR() Returns the position of the first occurrence of a substring within a string.

Example:

SELECT INSTR('Hello World’, 'World') AS Position;

(iii) SUBSTR()
Answer:
SUBSTR() Extracts a substring from a string starting at a specified position and length.

Example:

SELECT SUBSTR('Hello World', 7, 5) AS Substring;

(iv) MONTHNAME()
Answer:
MONTHNAMEO Returns the name of the month for a given date.

Example:

SELECT MONTHNAME('2024-09-07') AS MonthName:

(v) MOD()
Answer:
MOD() Returns the remainder of a division operation.

Example:

SELECT MOD(29, 5) AS Remainder;