1. 

Which Jessie Reyez track put her on Billie Eilish's radar?

2. 

Where did Shawn Mendes and Niall Horan first meet?

3. 

How many tracks have The Weeknd and Lana Del Rey worked on together?

4. 

What year did Taylor Swift and Selena Gomez first become friends?

5. 

Troye Sivan appeared in Ariana Grande's music video for...?

6. 

What was the name of Post Malone's 2016 collab with Justin Bieber?

7. 

Lady Gaga and Elton John collaborated on which 'Chromatica' track...?

8. 

Demi Lovato and Sam Smith collaborated on which track...?