Cross word puzzle

123456789101112131415161718
Across
  1. 4. The most abundant naturally occurring gas
  2. 5. Computers calculate numbers in what mode?
  3. 9. A square matrix that is not invertible
  4. 10. Bleaching action of chlorine is by
  5. 12. The set of its possible inputs
  6. 13. Study of generalizations of arithmetic operation
  7. 15. The first graphical browser for the WWW was named
  8. 16. A measure of speed in a given direction
  9. 17. Unit of Power
  10. 18. A computer virus that actively attacks an anti-virus program or programs in an effort to prevent detection is:
Down
  1. 1. Most abundant element in earth crust
  2. 2. Father of modern chemistry
  3. 3. Another word for the CPU is
  4. 6. Nuclear sizes are expressed in a unit named
  5. 7. To arrange information numerically/alphabetically
  6. 8. The heaviest metal
  7. 11. Triangle with two sides of the same length?
  8. 13. The device that measures current in a circuit
  9. 14. Well defined collection of distinct objects