Fill in the blanks to make the following statements true: (a) (–2) + (............) = (–5) + (............)
(b) 21 + ............ = 0 [2 marks]
Fill in the blanks to make the following statements true: \( [13 + (- 12)] + () = 13 + [(- 12) + (- 7)]\)
Fill in the blanks to make the following statements true: (i) (–2) + (............) = (–5) + (............)
(ii) –5 + ............ = –5 (iii) 21 + ............ = 0