Computer Science (Python) Set 4 2021-2022 Commerce (English Medium) Class 12 Question Paper Solution

"Stack is a linear data structure which follows a particular order in which the operations are performed."

What is the order in which the operations are performed in a Stack?

Name the List method/function available in Python which is used to remove the last element from a list implemented stack.

Also write an example using Python statements for removing the last element of the list.

Expand the following:

VoIP

Expand the following term:

PPP

Riya wants to transfer pictures from her mobile phone to her laptop. She uses Bluetooth technology to connect two devices. Which type of network (PAN/LAN/MAN/WAN) will be formed in this case?

Differentiate between the terms Attribute and Domain in the context of Relational Data Model.

Consider the following SQL table MEMBER in a SQL Database CLUB:

          Table: MEMBER

Assume that the required library for establishing the connection between Python and MYSQL is already imported in the given Python code. Also assume that DB is the name of the database connection for table MEMBER stored in the database CLUB.

Predict the output of the following code :

MYCUR = DB.cursor() 
MYCUR.execute ("USE CLUB") 
MYCUR.execute ("SELECT * FROM MEMBER WHERE ACTIVITY= 'GYM' ") 
R=MYCUR.fetchone() 
for i in range(2) :
      R=MYCUR.fetchone() 
      print (R[0], R[1], sep = "#")

Write the output of SQL queries (a) to (d) based on the table VACCINATION_DATA given below:

                              Table: VACCINATION_DATA

1. SELECT Name, Age FROM VACCINATION_DATA
WHERE Dose2 IS NOT NULL AND Age > 40;
2. SELECT City, COUNT(*) FROM VACCINATION_DATA GROUP BY City;
3. SELECT DISTINCT City FROM VACCINATI ON_ DATA;
4. SELECT MAX(Dose1), MIN(Dose2) FROM VACCINATION_ DATA;

Write the output of SQL queries (a) and (b) based on the following two tables DOCTOR and PATIENT belonging to the same database:

        Table: DOCTOR

                 Table: PATIENT

1. SELECT DNAME, PNAME FROM DOCTOR
NATURAL JOIN PATIENT;
2. SELECT PNAME, ADMDATE, FEES
FROM PATIENT P, DOCTOR D
WHERE D.DNO = P.DNO AND FEES > 1000;

Differentiate between Candidate Key and Primary Key in the context of Relational Database Model.

Consider the following table PLAYER: 

         Table: PLAYER

1. Identify and write the name of the most appropriate column from the given table PLAYER that can be used as a Primary key.
2. Define the term Degree in relational data model. What is the Degree of the given table PLAYER?

• Write the definition of a user defined function PushNV(N) which accepts a list of strings in the parameter N and pushes all strings which have no vowels present in it, into a list named NoVowel.
• Write a program in Python to input 5 words and push them one by one into a list named All.
  The program should then use the function PushNV() to create a stack of words in the list NoVowel so that it stores only those words which do not have any vowel present in it, from the list All. Thereafter, pop each word from the list NoVowel and display the popped word. When the stack is empty display the message "EmptyStack".

For example:

If the Words accepted and pushed into the list All are

['DRY', 'LIKE', 'RHYTHM', 'WORK', 'GYM']

Then the stack No Vowel should store

['DRY', 'RHYTHM', 'GYM']

And the output should be displayed as

GYM RHYTHM DRY EmptyStack

• Write the definition of a user defined function Push3_5 (N) which accepts a list of integers in a parameter N and pushes all those integers which are divisible by 3 or divisible by 5 from the list N into a list named Only3_5.
• Write a program in Python to input 5 integers into a list named NUM.
  The program should then use the function Push 3_5() to create the stack of the list Only3_5. Thereafter pop each integer from the list Only3_5 and display the popped value. When the list is empty, display the message "StackEmpty".

For example:

If the integers input into the list NUM are:

[10, 6, 14, 18, 30]

Then the stack Only3_5 should store

[10, 6, 18, 30]

And the output should be displayed as

30 18 6 10 StackEmpty

A SQL table ITEMS contains the following columns:

INO, INAME, QUANTITY, PRICE, DISCOUNT

Write the SQL command to remove the column DISCOUNT from the table.

Categorize the following SQL commands into DDL and DML:

CREATE, UPDATE, INSERT, DROP

Rohan is learning to work upon Relational Database Management System (RDBMS) application. Help him to perform the following task:

To open the database named "LIBRARY".

Rohan is learning to work upon Relational Database Management System (RDBMS) application. Help him to perform the following task:

To display the names of all the tables stored in the opened database.

Rohan is learning to work upon Relational Database Management System (RDBMS) application. Help him to perform the following task:

To display the structure of the table "BOOKS" existing in the already opened database "LIBRARY".

Write SQL queries for (a) to (d) based on the tables PASSENGER and FLIGHT given below:

        Table: PASSENGER

                            Table: FLIGHT

1. Write a query to change the fare to 6000 of the flight whose FNO is F104.
2. Write a query to display the total number of MALE and FEMALE PASSENGERS.
3. Write a query to display the NAME, corresponding FARE and F_DATE of all PASSENGERS who have a flight to START from DELHI.
4. Write a query to delete the records of flights which end at Mumbai.

Differentiate between Bus Topology and Tree Topology.

Give one advantage of Bus topology.

Write one advantage of Tree Topology.

Write two points of difference between XML and HTML.

What is a Web Browser?

Write the names of any two commonly used Web Browsers.

Galaxy Provider Ltd. is planning to connect its office in Texas, USA with its branch at Mumbai. The Mumbai branch has 3 Offices in three blocks located at some distance from each other for different operations – ADMIN, SALES and ACCOUNTS. 

As a network consultant, you have to suggest the best network related solutions for the issues/problems raised in (a) to (d), keeping in mind the distances between various locations and other given parameters.

Layout of the Offices in the Mumbai branch:

Shortest distances between various locations:

Number of Computers installed at various locations are as follows:

1. It is observed that there is a huge data loss during the process of data transfer from one block to another. Suggest the most appropriate networking device out of the following, which needs to be placed along the path of the wire connecting one block office with another to refresh the signal and forward it ahead.
   1. MODEM
   2. ETHERNET CARD
   3. REPEATER
   4. HUB
2. Which hardware networking device out of the following, will you suggest to connect all the computers within each block?
   1. SWITCH
   2. MODEM
   3. REPEATER
   4. ROUTER
3. Which service/protocol out of the following will be most helpful to conduct live interactions of employees from Mumbai Branch and their counterparts in Texas?
   1. FTP
   2. PPP
   3. SMTP
   4. VoIP
4. Draw the cable layout (block to block) to efficiently connect the three offices of the Mumbai branch.