"General Knolwdge": HTML5 Crossword

Across

3. The highest city in the world (5)
4. The largest county in Ireland (4)
8. Individual bones found in the spine (9,0)
9. The atomic a particle with a neutral charge (7)
10. The football team with the most Champions League titles (10)
12. Place in China that was the origin of Covd-19 (5)
15. The name given to the perimeter of a circle (13,0)
16. Rockstar's best selling game (15)
17. The name of valley's formed by moving glaciers (13)
18. What does TKO mean? (17)
19. Famous boating shoes worn by fee paying school goers (8)
20. 8 x 4 - (25-7) = (8)

Down

1. The state Sleepy Joe Biden lives in (8)
2. The gas most of Earth's atmosphere is formed of (8)
5. Scientist who was hit in the head by a falling apple (11)
6. Positively charged atomic particle (6)
7. Arnold Schwarzenegger's country of birth (7)
11. The largest land mammal on Earth (15)
13. The rugby team with the most Champions Cup titles (8)
14. The 19th element on the periodic table (9)