Could someone confirm broken links (plus two other doubts)

rontiv

1. I went over the course during the last week and I found this broken links:

On lesson 04. Installing Linux > Linux Installation >> Installation Choices
"Oracle VirtualBox" https://www.oracle.com/virtualization/solutions/try-oracle-vm-virtualbox/

On lesson 09. Security Fundamentals >> Securing Linux > Least Privilege
"least privilege" https://www.cisa.gov/bsi/articles/knowledge/principles/least-privilege

On lesson 11. Supporting Applications and Developers > Software Project Management >> Waterfall or Sequential Project Management
"slack time" https://www.productiveedge.com/2015/06/29/slack-time-the-nature-of-the-beast/ (note: this one doesn't show any errors but it simple redirects to its blog home page)

On lesson 11. Supporting Applications and Developers > Software Application Architecture >> Frontend Architecture
"graphical user interface" https://www.omnisci.com/technical-glossary/graphical-user-interface

On lesson 11. Supporting Applications and Developers > Software Application Architecture >> Frontend Architecture
"How to create a scalable and maintainable front-end architecture " https://laptrinhx.com/how-to-create-a-scalable-and-maintainable-front-end-architecture-3542080245/

2. Addtiionally on lesson 04. Installing Linux > Linux Installation >> Using AWS or WSL/WSL2
   The "AMIs" acronym is mentioned without any link or explanation I guess it refers to "Amazon Machine Image", right?

3. Finally on 05. Linux Filesystems and File Management > Knowledge Check >> Question 5.4
   That says "Which of the following programs can convert a PC-DOS partitioned disk to a GPT partitioned disk?" the correct question is listed as "f" (None of the above) but I fail to understand where from the course material one can arrive to that conclusion/answer. I believe the most relevant part of the course on that same lesson is found at > "Storage Management and Configuration" >> "Storage Management and Configuration" and on the "Disk Formatting Utilities" parts or sections but still I didn't find the answer there.