HKDSE ICT Question Review (20241017)

1. In a PC with Windows 11 installed, if the desktop is idle for more than 5 minutes, the lock screen will appear. Suggest a method to bypass the lock screen.

Solution:

Write a powershell script that repeated emulation of pressing a keyboard button happens within the interval of no more than 299 seconds.

2. Given an Win11 account name you are using TORTOISE, suggest a method to obtain the password expiry date and export it.

Solution:

Press Win + R to launch run window, then type cmd and press enter to launch command prompt. Next, type the following command and press enter:

net user TORTOISE > C:\users\TORTOISE\desktop\password.txt

Then the result will be exported to a plain text file on your desktop.

You will see something like this from the password.txt file:

A small trick from Question 2:

You can type the following command to shorten the result by using find command at the same time:

C:\>net user TORTOISE| find "Password expires"

Password expires 21.04.12 13:44

3. A program Wechat.exe is running on your Win11 background. Suppose it has no administrator privileges, suggest a method to kill the process without using Task Monitor.

Solution:

In command prompt or when creating a shortcut, type the following command:

taskkill /f /im Wechat.exe

Note that if you wanna kill Windows Defender Anti-virus Service, you will get "Access is Denied" alert even if you log on as administrator. Yes, Win10 onwards is a bloatware having complete control of your PC.

Task Manager

4. How to read an PDF file without Adobe Acrobat DC installed?

Solution:

Office 365 app

OR

Samsung Notes app

OR from PC

Libreoffice Draw

OR from Desktop

Microsoft Edge

OR

Google Chrome

OR

Mozilla Firefox

OR

Foxit Reader

OR

PDFill PDF Editor Profesional

5. There are 2 jpeg photos of following colors:

Pic 1: Greyscale

Pic 2: 24-bit RGB

Explain why Pic 2 has a smaller file size.

Solution:

All bits are used for Greyscale, but 24-bit RGB is not. 24-bit = 2^24 bits while Greyscale uses 256 bits = 2^8 bits. By running heap sort as a compression algorithm, Pic 2 will show better efficiency and thus lower Big-O notations.