A. In the context of TCP/IP networks, the communication side that initiates a connection is called the client, whereas the side that answers the client is called the server.

This statement is true because TCP/IP networks use a client-server model to establish connection-oriented communications. The client is the device or application that requests a service or resource from another device or application, which is called the server. The server responds to the client’s request and provides the service or resource. For example, when you browse a website using a web browser, the browser acts as a client and sends a request to the web server that hosts the website.  The web server acts as a server and sends back the requested web page to the browser 1 .

B. Connectionless communications are usually built on top of TCP.

This statement is false because TCP (Transmission Control Protocol) is a connection-oriented protocol that requires establishing and terminating a connection before and after sending data. Connectionless communications are usually built on top of UDP (User Datagram Protocol), which is a connectionless protocol that does not require any connection setup or teardown. UDP simply sends data packets to the destination without checking if they are received or not 2 .

C. Using walkie-talkies is an example of a connection-oriented communication.

This statement is false because using walkie-talkies is an example of a connectionless communication. Walkie-talkies do not establish a dedicated channel or connection between the sender and receiver before transmitting data. They simply broadcast data over a shared frequency without ensuring that the receiver is ready or available to receive it.  The sender does not know if the receiver has received the data or not 3 .

D. A phone call is an example of a connection-oriented communication.

This statement is true because a phone call is an example of a connection-oriented communication. A phone call requires setting up a circuit or connection between the caller and callee before exchanging voice data. The caller and callee can hear each other’s voice and know if they are connected or not.  The phone call also requires terminating the connection when the conversation is over 4 .

References:

1 : https://www.techtarget.com/searchnetworking/definition/client-server  2 : https://www.javatpoint.com/connection-oriented-vs-connectionless-service  3 : https://en.wikipedia.org/wiki/Walkie-talkie  4 : https://en.wikipedia.org/wiki/Telephone_call

A is true because in the context of TCP/IP networks, the communication side that initiates a connection is called the client, and the side that answers the client is called the server. This is the basis for establishing a connection-oriented communication.

D is true because a phone call is an example of a connection-oriented communication. Like TCP/IP, a phone call establishes a connection between two devices (in this case, two phones) before communication can occur.

A is true because in the context of TCP/IP networks, the communication side that initiates a connection is called the client, and the side that answers the client is called the server. This is the basis for establishing a connection-oriented communication.

D is true because a phone call is an example of a connection-oriented communication. Like TCP/IP, a phone call establishes a connection between two devices (in this case, two phones) before communication can occur.

B is false because connectionless communications are usually built on top of UDP, not TCP. UDP is a connectionless protocol that does not establish a connection before sending data.

C is false because using walkie-talkies is an example of a connectionless communication. Walkie-talkies do not establish a connection before communication begins, and messages are simply broadcasted to all devices within range.

Here is a sample code in Python using the  socket  module to create a TCP server and client to demonstrate the connection-oriented communication:

Server-side code:

import socket

HOST = '127.0.0.1'

PORT = 8080

with socket. socket (socket.AF_INET, socket.SOCK_STREAM) as s:

s. bind ((HOST, PORT))

s. listen ()

conn, addr = s. accept ()

with conn:

print ( 'Connected by' , addr)

while True:

data = conn. recv ( 1024 )

if not data:

break

conn. sendall (data)

Client-side code:

import socket

HOST = '127.0.0.1'

PORT = 8080

with socket. socket (socket.AF_INET, socket.SOCK_STREAM) as s:

s. connect ((HOST, PORT))

s. sendall (b ' Hello, world ' )

data = s. recv ( 1024 )

print ( 'Received' , repr (data))

The server listens for incoming connections on port 8080, and when a connection is established, it prints the address of the client that has connected. The server then continuously receives data from the client and sends it back to the client until the connection is closed.

The client establishes a connection with the server and sends the message "Hello, world" encoded as bytes. It then waits for a response from the server and prints the data it receives.

The correct answers are  A. An attribute owned by every exception object  and  D. An attribute that holds interesting information that is particularly useful when the programmer wants to store exception details in other objects . A traceback is an attribute of an exception object that contains a stack trace representing the call stack at the point where the exception was raised. The traceback attribute holds information about the sequence of function calls that led to the exception, which can be useful for debugging and error reporting.

The  @property  decorator should be defined after the method that is responsible for setting an encapsulated attribute is a false sentence. In fact, the  @property  decorator should be defined before the method that is used to set the attribute value. The  @property  decorator and the setter and deleter methods work together to create an encapsulated attribute, which is used to provide control over the attribute's value.

A static method is a method that belongs to a class rather than an instance of the class. It is defined using the  @staticmethod  decorator and does not take a  self  or  cls  parameter. Static methods are often used to define utility functions that do not depend on the state of an instance or the class itself.

A socket object is usually created using the socket() constructor provided by the socket module in Python. The correct invocation is  socket.socket(socket_domain, socket_type) . This creates a new socket object with the specified socket domain and type.

If the main window is too small to fit all its widgets,  some widgets may be invisible . So, the correct answer is  Option A .

When a window is not large enough to display all of its content, some widgets may be partially or completely hidden. The window will not automatically expand to fit all of its content, and no exception will be raised. The widgets will not be automatically scaled down to fit the window’s size.

If the main window is too small to fit all its widgets, some of the widgets may not be visible or may be partially visible. This is because the main window has a fixed size, and if there are more widgets than can fit within that size, some of them will be outside the visible area of the window.

To avoid this issue, you can use layout managers such as  grid ,  pack , or  place  to dynamically adjust the size and position of the widgets as the window changes size. This will ensure that all the widgets remain visible and properly arranged regardless of the size of the main window.

References:

https://www.tkdocs.com/tutorial/widgets.html#managers

https://www.geeksforgeeks.org/python-tkinter-widgets/

https://anzeljg.github.io/rin2/book2/2405/docs/tkinter/introduction.html

The  messagebox.askquestion()  method in Python's tkinter library displays a message box with a specified question and two response buttons labeled "Yes" and "No". It returns a string indicating which button was selected - either "yes" or "no".

This function is used to ask questions to the user that have only two options: YES or NO.  It can be used to ask the user if they want to continue or if they want to submit something  1 .

The unbind_all() method in Tkinter is used to remove all event bindings from a widget. It is a method of the widget object and can be called on any widget in the Tkinter application. Therefore, option A is the correct answer.

Option B is incorrect because the method can be called on any widget, not just the main window widget.

Option C is correct as unbind_all() does not take any parameters.

Option D is incorrect because the method only removes event bindings and does not cause the widgets to disappear.

So, the correct answers are A and C.

References:

Tkinter documentation:  https://docs.python.org/3/library/tkinter.html#event-bindings

Tkinter tutorial:  https://www.python-course.eu/tkinter_events_binds.php

The json.dumps() function is used to convert a Python object into a JSON string  1 . It takes Python data as its argument, such as a dictionary or a list, and returns a JSON string.

Option B is correct because it sets the font option of the button to a tuple containing the font family (‘Arial’), size (12), and style (‘italic’).

Option C is correct because it sets the font option of the button to a string containing the font family (‘Arial’), size (12), and style (‘italic’) separated by spaces.