1. How do you define AI?
I define Ai as the simulation of human intelligence processes by machines, particularly computer systems.
https://www.techtarget.com/searchenterpriseai/definition/AI-Artificial-Intelligence#:~:text=Artificial%20intelligence%20is%20the%20simulation,speech%20recognition%20and%20machine%20vision.

2. Can you name at least three different sub-fields of AI?
Machine learning, robotics, neural networks etc...

3. AI has been around since about 70 years so far. Why is it booming right now?
AI has become more popular today due to increased data volumes, advanced algorithms, and improvements in computing power and storage.
https://www.sas.com/en_in/insights/analytics/what-is-artificial-intelligence.html
https://www.theverge.com/2018/12/12/18136929/artificial-intelligence-ai-index-report-2018-machine-learning-global-progress-research
https://www.wired.com/insights/2015/03/ai-resurgence-now/

4. Can you name at least three application sectors where robots are being largely employed? What are the reasons? 
Robots are being widely used in sectors such as manufacturing, agriculture, and entertainment. The reasons are that robots are usually implemented in monotonous tasks that requires a lot of precision because in such situations, robots are better suited than humans because they are precise, intelligent, and don’t get bored.
https://www.geeksforgeeks.org/top-10-applications-of-robotics-in-2020/

5.Can you identify three major challenges for a wheeled autonomous robot performing a 24h surveillance task in a large facility? (e.g., something like Mall of Qatar)
The robot can be tricked by intruders if they known the functions and algorithms the robots use. They are also at this current stage at least, difficult to talk with and unable react to sudden unexpected scenarios outside of their program.