Students must start practicing the questions from CBSE Sample Papers for Class 12 Informatics Practices with Solutions Set 9 are designed as per the revised syllabus.
CBSE Sample Papers for Class 12 Informatics Practices Set 9 with Solutions
Time Allowed: 3 hours
Maximum Marks: 70
General Instructions:
- This question paper contains five sections, Section A to E.
- All questions are compulsory.
- Section A has 18 questions carrying 01 mark each.
- Section B has 07 Very Short Answer type questions carrying 02 marks each.
- Section C has 05 Short Answer type questions carrying 03 marks each.
- Section D has 02 questions carrying 04 marks each.
- Section E has 03 questions carrying 05 marks each.
- All programming questions are to be answered using Python Language only.
Section – A
Question 1.
Which of the following is not a type of Cyber crime? [1]
(a) Data theft
(b) Forgery of online documents
(c) Damage to data and systems
(d) Installing antivirus for protection
Answer:
(d) Installing antivirus for protection
Question 2.
A/An _____ is a unique data trace of a user’s activities, actions, communications or transactions in digital media. [1]
(a) digital handprint
(b) digital footprint
(c) offline footprint
(d) offline handprint
Answer:
(b) digital footprint
Question 3.
Pandas series is ____. [1]
(a) two dimensional
(b) three dimensional
(c) one dimensional
(d) multi-dimensional
Answer:
(c) one dimensional
Question 4.
____ are the impact of e-Waste of the environment. [1]
(a) Soil pollution
(b) Water pollution
(c) Air pollution
(d) Sound pollution
Answer:
(d) Sound pollution
Question 5.
The AVG() function in MySQL is an example of [1]
(a) MATH() function
(b) TEXT() function
(c) DATE() function
(d) Aggregate function
Answer:
(d) Aggregate function
Question 6.
Out of the following, which function cannot be used for customisation of charts in Python?
(a) xlabel()
(b) color()
(c) title()
(d) xticks()
Answer:
(b) color()
Question 7.
‘F’ in FOSS stands for ____. [1]
(a) Free
(b) Forever
(c) Fire
(d) Freezing
Answer:
(a) Free
Question 8.
While accessing the column from the DataFrame, we can specify the column name. In case column does not exist, which type of error it will raise? [1]
(a) Key error
(b) Syntax error
(c) Name error
(d) Runtime error
Answer:
(a) Key error
Question 9.
____ is a collection of independent computers and other hardware interconnected by communication channels. [1]
(a) Computer
(b) Networking
(c) Sharing
(d) None of these
Answer:
(b) Networking
Question 10.
Table: DEPARTMENT
DEPT CODE | DEPTNAME | PLACE |
D01 | CSE | MUMBAI |
D02 | IT | KOLKATA |
D04 | MEDIA | DELHI |
D03 | HR | MUMBAI |
D05 | SALES | DELHI |
Write the output of the following statement.
SELECT COUNT(DISTINCT DEPTNAME) FROM DEPARTMENT;
(a) 5
(b) 4
(c) 3
(d) Error
Answer:
(a) 5
Question 11.
Modulation and demodulation is performed by ___. [1]
(a) microwave
(b) satellite
(c) modem
(d) gateway
Answer:
(c) modem
Question 12.
If on ‘1990-01-22’, it was Monday, what will be the output of following SQL command?
SELECT dayname (‘1990-01-22’)+1; [1]
(a) Error
(b) 1
(c) 7
(d) Monday
Answer:
(b) 1
Question 13.
Which of the following is not a violation of IPR? [1]
(a) Plagiarism
(b) Copyright infringement
(c) Patent
(d) Trademark infringement
Answer:
(c) Patent
Question 14.
In MySQL, Reena and Zebi are getting the following output of SELECT statement on a table Employee. [1]
Which keyword has Zebi used with a SELECT statement to get the above output?
(a) COUNT
(b) UNIQUE
(c) DISTINCT
(d) All of these
Answer:
(c) DISTINCT
Question 15.
Consider the following query [1]
SELECT * FROM employee ORDER BY salary ____, name _____:
To display the salary from greater to smaller and name in alphabetical order which of the following options should be used ?
(a) Ascending, Descending
(b) Asc, Desc
(c) Desc, Asc
(d) Descending, Ascending
Answer:
(c) Desc, Asc
Question 16.
In which function, NULL values are excluded from the result returned? [1]
(a) SUM()
(b) MAX()
(c) MIN()
(d) All of these
Answer:
(d) All of these
Directions (Q.Nos. 17-18) Assertion and Reason based Questions.
Question 17.
Assertion (A) The bus topology is prone to data collisions. [1]
Reason(R) In a bus topology, all devices share the same communication medium, leading to data collisions when two devices transmit data simultaneously.
(a) Both A and R are True and R is the correct explanation of A.
(b) Both A and R are True and R is the not correct explanation of A.
(c) A is true but R is False.
(d) A is False but R is true.
Answer:
(a) Both A and R are true and R is the correct explanation of A.
Question 18.
Assertion (A) Elements of Series can be accessed using positional index. [1]
Reason (R) Positional index values ranges from 1 to n, if n is the size of the series.
(a) Both A and R are true and R is the correct explanation of A.
(b) Both A and R are ture but R is not the correct explanation of A
(c) A is true but R is false.
(d) A is false but R is true.
Answer:
(c) Elements of the series can be accessed using positional index, positional index values start from 0 and it ranges from 0 to n-1, if n is the size of the series. Hence, A is true but R is false.
Section – B
Question 19.
Navya has just created a website for her company and now need to host it. Briefly discuss the role of a web server in hosting a website. [2]
Or
Write one advantage each of star and bus topology used in networking. Draw a network layout of bus topology to connect six computers.
Answer:
A web server is the residence of web pages. It is also the agent that fetches the web pages when the web pages are requested by clients. The main job of a web server is to display website content through storing, processing and delivering web pages to users. All computers that host websites must have web server software. Web servers are used in web hosting or the hosting of data for websites and web-based applications or web applications.
Or
Advantage of star topology is that it is most reliable as there is a direct connection of every node with the central node or server.
Advantage of bus topology is that all nodes are connected through a single length of a cable, so very short cable length is used.
A network layout of bus topology to connect six computers is as follows:
Question 20.
Mr. Roy is a manager in a hotel and wants to find out some data from a table, where he maintains the hotel records. He is not very expert with SQL commands and functions. Help him to write the queries. [2]
Table: Hotel
RoomId | CName | RoomType | DtofArrival | Charges |
R1 | Ritesh | AC | 2016-09-09 | 1800 |
R2 | Suman | Deluxe | 2020-08-01 | 2000 |
R3 | Abhi | General | 1995-04-05 | 3000 |
R4 | Ram | AC | 1994-02-02 | 2500 |
R5 | Nitin | Deluxe | NULL | 7000 |
(i) Display count of the different room types from the table Hotel.
(ii) Display the average room charges of “AC” rooms.
Answer:
(i) SELECT COUNT(DISTINCT RoomType) From Hotel;
(ii) SELECT AVG(Charges) FROM Hotel WHERE RoomType=“AC”;
Question 21.
What is the purpose of GROUP BY clause in MySQL? How is it different from ORDER BY clause? [2]
Answer:
The GROUP BY clause can be used to combine all those records that have identical value in a particular field or a group of fields.
Whereas, ORDER BY clause is used to display the records either in ascending or descending order based on a particular field. For ascending order, ASC is used and for descending order DESC is used. The default order is ascending order.
Question 22.
The Python code written below has syntactical errors. Rewrite the correct code and underline the corrections made. [2]
import pandas as pd data = {Name [‘Riya', ‘Preeti'. 'Neeta'], 'Age': [25, 30, 22]} df = pd.DataFrame(Data) for row in df: print(row)
Answer:
Correct code is:
Import pandas as pd data = {'Name': ['Riya', 'Preeti’, 'Neeta’], 'Age': [25, 30, 22]} df = pd.DataFrame(data) for index, row in df.iterrows( ): print(row)
Question 23.
What is data protection? List two ways to protect your data. [2]
Answer:
Data protection refers to the practices, safeguards and binding rules that ensure protection of sensitive and personal information.
Two ways of data protection are as follows:
- By data encryption
- Not opening phishing E-mails
Question 24.
What will be the output of the given code? [2]
import pandas as pd ” s = pd.Series[1, 2, 3, 4, 5], index=[‘akram’, ‘brijesh’, ‘charu’, ‘deepika’, ‘era’]) print(s[ 'charu’])
Answer:
The code print(s[‘charu’]) prints the value at
index ‘charu’ which is 3.
Question 25.
Complete the given Python code: Create a pandas Series from a scalar value ‘10’ and display the last 3 elements of the Series. [2]
import ____ as pd series_data = pd.Series(____) print(series___data.(____))
Answer:
Code is
import pandas as pd series_data = pd.Series(10) print(series_data.tail(3))
Section – C
Question 26.
Write a output for SQL queries (i) to (iii), which are based on the table Student given below: [3]
Table: Student
(i) SELECT COUNT(*), City FROM Student GROUP BY City HAVING COUNT( *)>1;
(ii) SELECT MAX (DOB), MIN (DOB) FROM Student;
(iii) SELECT NAME,GENDER FROM Student WHERE City= “Delhi ”;
Answer:
Question 27.
Rahul has written a code with a DataFrame and a CSV file “Emp.csv” containing records of employees as follows: [3]
Index | Eno | Ename | Eage | Esal |
0 | 1 | Ritesh | 15 | 5600 |
1 | 2 | Aakash | 16 | 17000 |
2 | 3 | Sumit | 17 | 12500 |
3 | 4 | Ria | 20 | 18000 |
Write the Python code to read the data from the CSV file, display its first two records and then rewrite the data to a new CSV file.
Answer:
import pandas as pd empdf=pd.read_csv(‘C: \\Data\\Emp.csv ’) empdf.head(2) empdf .tocsv(‘C:\\Data\\Empnew.csv’)
Question 28.
Given a DataFrame ‘df ’ created as : [3]
Index | Roll | Name | Marks |
0 | 1 | Ravi | 56 |
1 | 2 | Sheeta | 77 |
2 | 3 | Paromita | 89 |
3 | 4 | Debarati | 98 |
Write the Python statements to :
(i) Get the output as ” 2 Paromita”.
(ii) Change the index order to 2,1,0.
(iii) See the data type of the ‘Marks’ column.
Answer:
(i) df.loc[2:, ‘Name’]
(ii) df.reindex([2, 1, 0])
(iii) df [‘Marks’].dtype
Question 29.
List the guidelines to avoid plagiarism. [3]
Or
What are the psychological problems related to the usage of technology?
Answer:
Follow the below guidelines to avoid plagiarism:
- To avoid plagiarism, instead of copying the language of the book as it is, try to put it is your own language/words.
- One should have a clear understanding of plagiarism and its consequences, so that no one perform it unintentionally.
- If copying someone else’s work in our task, word for word, then do not forget enclosing it is quotes and also mention its source.
- Another way is to credit the author has write which was useful for your task and not taking credit for its yourself.
Or
There are some psychological problems related to the usage of technology
- Egosurfing An illness of regularly reaching for one’s own name on the web and checking what information is available about one’s own on the net.
- Infornography The word, derived from pornography and information, describes the state of ‘‘trying to quiet hunger for information on the net”.
- Blog streaking A desire to spread information online that should not be known by everybody.
- Youtube egoism constantly uploading one’s own videos in order to introduce and make himself or herself known to others.
- Google stalking trying to get information about all his or her relatives or acquaintances in the web.
- Photo lurking Looking at the photoalbums of others on the net.
- Wikipedia holism Contributing to the internet encyclopedia, Wikipedia, sending someone’s own writings, and revising the present texts.
Question 30.
Consider the following table Games. Write SQL commands for the following statements.
Table:Games
GCode | GameName | Type | Number | PrizeMoney | ScheduleDate |
101 | Carom Board | Indoor | 2 | 5000 | 23/01/2004 |
102 | Badminton | Outdoor | 2 | 12000 | 12/12/2003 |
103 | Table Tennis | Indoor | 4 | 8000 | 14/02/2004 |
105 | Chess | Indoor | 2 | 9000 | 01/01/2004 |
108 | Lawn Tennis | Outdoor | 4 | 25000 | 19/03/2004 |
(i) To display the details of those Games, which are having PrizeMoney more than 7000.
(ii) To display sum of PrizeMoney for each Type of Games.
(iii) To display the total number of games available in the above table Games.
Or
Naina works for M/s Anish Steels Ltd. She has written following statements, but is not able to understand the outputs. Explain her the working of these statements and produce the outputs.
(i) SELECT INSTR(‘computerscience’,‘sc’);
(ii) SELECT MID(‘funandfood’, 3, 4);
(iii) SELECT ROUND( 1334.99); –
Answer:
(i) SELECT*FROM Games WHERE PrizeMoney > 7000;
(ii) SELECT SUM(PrizeMoney), Type FROM Games GROUP BY Type;
(iii) SELECT COUNT(GameName) FROM Games;
Or
Section – D
Question 31.
Consider the table given below and answer the questions [4]
Table :EMP
(i) To display EMPNO, ENAME, SEX from the table EMP in descending order of EMPNO
(ii) To display the records of all female employee from the table EMP.
(iii) To display the EMPNO and ENAME of those employees from the table EMP who are joined between ’2011-01-01’ and ‘2013-01-01’.
(iv) To count the number of male employees who have bom before ‘1994-01-01’.
Answer:
(i) SELECT EMPNO, ENAME, SEX FROM EMP ORDER BY EMPNO DESC;
(ii) SELECT * FROM EMP WHERE SEX = ‘ F’ ;
(iii) SELECT EMPNO, ENAME FROM EMP WHERE DOJ BETWEEN ‘2011-01-01’ AND ‘2013-01-01’;
(iv) SELECT COUNT(EMPNO) FROM EMP WHERE SEX= ‘M’ AND DOJ < ‘1994-01-01’;
Question 32.
Jacqueline has created the following DataFrame consisting of data of houses of a school and the number of boys in the houses, shown as follows. She wants to perform certain operation on the data set. Help her with the correct actions. [4]
House
Index | Housename | Location | Boys |
0 | Ganga | East | 20 |
1 | Yamuna | West | 30 |
2 | Saraswathi | North | 56 |
(a) What will be the output of the following code?
(i) print(House.shape)
(ii) House.pop(“Location”)
print(House)
(b) She wants the “Housename” column to be the index of the DataFrame. What statement she should write? ‘
(c) To display total number of elements in the dataframe.
Or (Option for part (c) only)
She wants to see the number of columns. Write the statement which will display the number of columns.
Answer:
(a) (i) (3, 3)
(ii) House
Index | Housename | Boys |
0 | Ganga | 20 |
1 | Yamuna | 30 |
2 | Saraswati | 56 |
(b) House.set_index(‘Housename’)
(c) House, size
Or
Ten(House.columns)
Section – E
Question 33.
Given below a table Bookhouse, write SQL query for part (i) to (v). [5]
Table: Bookhouse
(i) Display Publisher wise total stock value (Qty * Price).
(ii) Display Title of the book which is costliest.
(iii) Display number of books and total Price for each type of Publisher.
(iv) Display all the books where subject starts with “D” and Qty is less than 3.
(v) Display all information of books whose Price starts with 2.
Or
Write the uses of following MySQL functions with one example of each.
(i) MID
(ii) LEFT()
(iii) TRIM()
(iv) LCASE()
(v) MAX()
Answer:
(i) SELECT Publisher, Qty*Price AS Total_Stock_Val ue FROM Bookhouse GROUP BY Publisher;
(ii) SELECT Title FROM Bookhouse WHERE Price=MAX(Price);
(iii) SELECT COUNT(*), SUM(Price) FROM Bookhouse GROUP BY Publisher;
(iv) SELECT Title FROM Bookhouse WHERE Subject LIKE ‘D%’ AND Qty<3;
(v) SELECT * FROM Bookhouse WHERE Price LIKE ‘2%’;
Or
(i) MID() This function returns a substring of the specified length starting from the specified position.
e.g. SELECT MID(‘HELLO ’, 3);
Output
(ii) LEFT() This function returns the left most number of characters as specified. e.g. SELECT LEFT ( ‘ HELLO ’, 1);
Output
(iii) TRIM() It removes any extra spaces from right and left of a string but not from the middle, e.g. SELECT TRIM (‘ Zebra crossing ’);
Output
(iv) LCASE() This function converts the characters of an argument string to the lowercase characters. e.g. SELECT LCASE (“Vowel”);
Output
(v) MAX() This function returns the largest value from the selected columns. Syntax SELECT MAX(column_name) FROM table_name;
e.g. Write a query to display the maximum pay availed by the coaches.
mysql> SELECT MAX (Pay) FROM Club;
Question 34.
China Middleton Fashion is planning to expand their network in India, starting with two cities to provide infrastructure for distribution of their products. [5]
The company has planned to setup their main office in Chennai at three different locations and have named their offices as Production Unit, Finance Unit and Media Unit. The company has its Corporate Unit in Delhi.
A rough layout of the same is as follows:
Approximate distance between these units is as follows:
From | To | Distance |
Product Unit | Finance Unit | 70 m |
Product Unit | Media Unit | 15 m |
Production Unit | Corporate Unit | 2112 m |
Finance Unit | Media Unit | 15 m |
In continuation of the above, the company experts have planned to install the following number of computers in each of these units.
To | Distance |
Production Unit | 150 |
Finance Unit | 35 |
Media Unit | 10 |
Corporate Unit | 30 |
(i) Suggest the kind of network required (out of LAN, MAN, WAN) for each of the following units.
(a) Production Unit and Media Unit
(b) Production Unit and Finance Unit
(ii) Which of the following devices will you suggest for connecting all computers with each of their office units?
(a) Switch/Hub
(b) Modem
(c) Telephone
(iii) Suggest a cable/wiring layout for connecting the company’s local office units located in Chennai.
(iv) After setting up the lab and Internet in the lab, company now requires to enable videos and animations to be played on the web browser for it’s employees. Which browser tool /service can be used for the same?
(v) Give an example of Open Source web browser.
Answer:
(i) (a) The type of network between the Production Unit and Media Unit is LAN (Local Area Network).
(b) The type of network between Production Unit and Finance Unit is MAN (Metropolitan Area Network).
(ii) (a) The suitable device for connecting all the computers within each of their office units is switch/hub.
(iii) The cable/wiring layout for connection is as follows:
(iv) Add-ons browser tool/service can be used to enable videos and animations to be played on the web browser for students of multimedia class.
(v) Google Chrome, Firefox.
Question 35.
Write the Python code for the following graph which display the different style multiline in same plot. [5]
Or
Observe the below figure and write the Python code to get the output.
Answer:
import matplotlib.pyplot as plt x1 = [10, 20, 30] y1 = [20, 40, 10] x2 = [10, 20, 30] y2 = [40, 10, 30] plt.xlabe1(‘x - axis’) plt.ylabe1(‘y - axis’) plt.plot(x1, y1, color=‘black’, linewidth = 5, label = 'line-dotted', linestyle='dashed') plt.plot(x2, y2, color=‘magenta’, linewidth = 3, label = 'line2-dashed', linestyle='dotted') plt.title(“Plot with different styles”) plt.legend( ) plt.show( )
Or
import numpy as np import matplotlib.pyplot as pit X=np.arange(5) Y=[10, 26, 24, 3, 56] plt.bar(X, Y) plt.title("First Bar Graph”) plt.ylim(0, 100) plt.xlim(0, 10) plt.xlabel(‘x - axis ’) plt.ylabel(‘y - axis’) plt.xticks([0, 2, 4, 6]) plt.yticks([0, 20, 40, 60, 80]) plt.show()