Commerce (English Medium) इयत्ता १२ - CBSE Question Bank Solutions for Computer Science (Python)

How is tree topology different from bus topology?

What do you mean by a modem? Why is it used?

Explain the following device:

Switch

Explain the following device:

Repeater

Explain the following device:

Gateway

Explain the following device:

Router

Explain the following device:

NIC

Which communication mode allows communication in both directions simultaneously?

______ is a communication methodology designed to deliver both voice and multimedia communications over Internet protocol.

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

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’)

Quickdev, an IT based firm, located in Delhi is planning to set up network for its four branches within a city with its Marketing department in Kanpur. As a network professional, give solution to the questions, after going through the branches locations and other details which are given below: 

Distance between various branches is a follows:

Number of computers in each of the branches:

1. Suggest the most suitable place to install the server for the Delhi branch with a suitable reason.
2. Suggest an ideal layout for connecting all these branches within Delhi.
3. Which device will you suggest, that should be placed in each of these branches to efficiently connect all the computers within these branches?
4. Delhi firm is planning to connect to its Marketing department in Kanpur which is approximately 300 km away. Which type of network out of LAN, WAN, or MAN will be formed? Justify your answer.
5. Suggest a protocol that shall be needed to provide help for transferring of files between Delhi and Kanpur branch.

The modem at the sender’s computer end acts as a ______.

What is the use of a raise statement? Write a code to accept two numbers and display the quotient. Appropriate exception should be raised if the user enters the second number (denominator) as zero (0).

Differentiate between readline() and readlines().

Write the use and syntax for the following method:

read()

Use assert statement in Question No. 3 to test the division expression in the program.

Why foreign keys are allowed to have NULL values? Explain with an example.

Differentiate between Primary key and foreign key.

A school has a rule that each student must participate in a sports activity. So each one should give only one preference for sports activity. Suppose there are five students in a class, each having a unique roll number. The class representative has prepared a list of sports preferences as shown below. Answer the following:

1. Roll no 24 may not be interested in sports. Can a NULL value be assigned to that student’s preference field?
2. Roll no 17 has given two preference sports. Which property of relational DBMC is violated here? Can we use any constraint or key in the relational DBMS to check against such violations, if any?
3. Kabaddi was not chosen by any student. Is it possible to have this tuple in the Sports Preferences relation?