Across
- 1. empty
- 5. mole
- 6. truth value
- 9. luminous intensity
- 11. four
- 12. commutative group
- 15. earth
- 16. Hindu-Arabic numeration system
- 17. neither positive nor negative
- 18. focal point of a circle
- 20. binary
- 21. six
- 22. collection
- 23. 1,500
Down
- 1. nothing
- 2. reasoning
- 3. spherical object
- 4. 2k
- 7. theorem which establishes congruence between triangles
- 8. ten-sided polygon
- 10. common notion
- 13. to transform into a coded message
- 14. basic unit for electric current
- 15. a mathematical system
- 18. cryptography
- 19. 500 pieces of bond paper
- 22. Systeme International d' Unites