2. The rational number whose square is 8 1 is (9), and the number whose reciprocal equals itself is (1).

3. If A and B are antonyms and M and N are reciprocal, then the square n of (a+b) +m = (1).

4. If the square of |x- 1|+(y+2) is 0, then the power of (x+y) is 2005 =(- 1).