CLEAN : Armed with rags, French railway staff disinfect trains

What is one of the topics mentioned in the first section?

• Selective transferability

• Graph theory

• Online communication

• Sunday events

Which of the following is NOT mentioned in the first section?

• Doctors

• Valuable metals

• Masks

• Graph theory

Which concept is discussed in the second section?

• Public keys

• Valuable metals

• Graph theory

• Contamination

What is a theme mentioned in the final section?

• Selective transferability

• Valuable metals

• Public keys

• Contamination

What is a topic discussed towards the end of the video?

• Masks

• Valuable metals

• Online communication

• Public keys