Why networks enable communication in Intro to Computing - Test Your Understanding

Practice - 5 Tasks

1fill in blank

easy

Complete the code to show how devices connect in a network.

Intro to Computing

devices = ['Computer', 'Phone', 'Printer']
network = [1](devices)
print(network)

Drag options to blanks, or click blank then click option'

Aset

Blist

Cdict

Dtuple

Attempts:

3 left

💡 Hint

Common Mistakes

Using a set which does not keep order.

Using a dict which needs key-value pairs.

The list type is used here to group devices in a network because it keeps the order and allows duplicates, just like devices connected in a network.

2fill in blank

medium

Complete the code to send a message from one device to another.

Intro to Computing

def send_message(sender, receiver, message):
    print(f"{sender} sends to {receiver}: {message}")

send_message('Phone', 'Computer', [1])

Drag options to blanks, or click blank then click option'

A'Hello!'

BHello

Cmessage

Dsend

Attempts:

3 left

💡 Hint

Common Mistakes

Forgetting quotes around the message.

Using a variable name that is not defined.

The message must be a string, so it needs quotes like 'Hello!'.

3fill in blank

hard

Fix the error in the code that simulates devices communicating in a network.

Intro to Computing

network = {'Computer': 'Online', 'Phone': 'Offline'}
status = network.get([1])
print(status)

Drag options to blanks, or click blank then click option'

A'Phone'

B'Tablet'

CPhone

DTablet

Attempts:

3 left

💡 Hint

Common Mistakes

Using a variable name without quotes.

Using a key not in the dictionary.

The key must be a string matching the dictionary keys, so it needs quotes like 'Phone'.

4fill in blank

hard

Fill both blanks to create a dictionary showing device statuses and check if a device is online.

Intro to Computing

devices_status = [1](Computer='Online', Phone='Offline')
if devices_status.get('Computer') == [2]:
    print('Computer is connected')

Drag options to blanks, or click blank then click option'

Adict

B'Online'

C'Offline'

Dlist

Attempts:

3 left

💡 Hint

Common Mistakes

Using list instead of dict.

Comparing to 'Offline' instead of 'Online'.

dict creates the dictionary. The status to check is the string 'Online'.

5fill in blank

hard

Fill all three blanks to create a dictionary comprehension that maps devices to their status if they are online.

Intro to Computing

devices = ['Computer', 'Phone', 'Printer']
statuses = {'Computer': 'Online', 'Phone': 'Offline', 'Printer': 'Online'}
online_devices = { [1]: [2] for [3] in devices if statuses[[3]] == 'Online' }

Drag options to blanks, or click blank then click option'

Adevice

Bstatuses[device]

Dstatus

Attempts:

3 left

💡 Hint

Common Mistakes

Using a variable name not defined in the loop.

Mixing up keys and values in the comprehension.

The comprehension uses device as the key and statuses[device] as the value. The loop variable is also device.

Practice

1. Why do networks enable communication between devices?

easy

A. Because devices do not need rules to communicate

B. Because devices work only when disconnected

C. Because networks block all messages

D. Because they connect devices to share information

Solution

1. Step 1: Understand the role of networks

   Networks connect different devices like computers and phones so they can share data.

2. Step 2: Identify the purpose of connection

   Sharing information is only possible when devices are connected through a network.

3. Final Answer:

   Because they connect devices to share information -> Option D

4. Quick Check:

   Networks connect devices = communication [OK]

Hint: Networks connect devices to share data quickly [OK]

Common Mistakes:

• Thinking devices communicate without connection
• Believing networks block messages
• Ignoring the need for connection

2. Which of the following is the correct way networks send messages safely?

easy

A. By following rules called protocols

B. By using random guesses to send data

C. By ignoring errors in messages

D. By sending messages without addresses

Solution

1. Step 1: Identify how networks send messages

   Networks use special rules called protocols to send messages correctly and safely.

2. Step 2: Understand the importance of protocols

   Protocols ensure messages reach the right device without errors.

3. Final Answer:

   By following rules called protocols -> Option A

4. Quick Check:

   Protocols = safe message sending [OK]

Hint: Protocols are rules networks follow to send messages [OK]

Common Mistakes:

• Thinking messages are sent by guessing
• Ignoring message errors
• Sending messages without addresses

3. Look at this simple flowchart of sending a message over a network:



What happens if the device is not connected?

medium

A. The message is sent anyway

B. The message is not sent

C. The device restarts automatically

D. The message is sent twice

Solution

1. Step 1: Follow the flowchart decision

   The flowchart checks if the device is connected before sending a message.

2. Step 2: Understand the outcome if not connected

   If the device is not connected, the message is not sent to avoid errors.

3. Final Answer:

   The message is not sent -> Option B

4. Quick Check:

   Not connected = no message sent [OK]

Hint: No connection means no message sent [OK]

Common Mistakes:

• Assuming message sends without connection
• Thinking device restarts automatically
• Believing message duplicates

4. This code tries to send a message over a network:

if connected = True:
    send_message()
else:
    print('No connection')

What is wrong with this code?

medium

A. The print statement is incorrect

B. It should use 'else if' instead of 'else'

C. It uses '=' instead of '==' to check connection

D. The send_message() function is missing parentheses

Solution

1. Step 1: Identify the condition syntax error

   The code uses '=' which assigns value instead of '==' which compares values.

2. Step 2: Explain correct comparison usage

   To check if connected is True, use '==' or simply 'if connected:'

3. Final Answer:

   It uses '=' instead of '==' to check connection -> Option C

4. Quick Check:

   Use '==' for comparison, '=' is assignment [OK]

Hint: Use '==' to compare, '=' assigns value [OK]

Common Mistakes:

• Using '=' instead of '==' in conditions
• Confusing else with else if
• Forgetting parentheses in function calls

5. A company wants to send a message from one office to another far away. Which network feature makes this possible?

hard

A. Networks use protocols to send messages over long distances

B. Networks only work within one room

C. Networks block messages to distant places

D. Networks require devices to be physically connected by wires only

Solution

1. Step 1: Understand network distance capability

   Networks can connect devices far apart using protocols and infrastructure like the internet.

2. Step 2: Identify how messages travel long distances

   Protocols and network devices route messages safely over long distances, not limited to wires or rooms.

3. Final Answer:

   Networks use protocols to send messages over long distances -> Option A

4. Quick Check:

   Protocols enable long-distance communication [OK]

Hint: Protocols enable messages to travel far [OK]

Common Mistakes:

• Thinking networks only work in one room
• Believing messages are blocked over distance
• Assuming only wired connections exist