Rational number

123456789
Across
  1. 4. a+b=b+a
  2. 6. ____had no reciprocals
  3. 8. The value of number which is greater than or equal to zero
  4. 9. property which does not hold true for division
Down
  1. 1. negative of a rational number
  2. 2. of 1 is 1
  3. 3. of a negative no and additive no is zero
  4. 5. 0+1=1+0=1
  5. 7. repeated addition