Given below are pairs of statements. In each case, combine them using 'if and only if'.
(i) `p:" In "Delta ABC, angleB = anlgeC.`
`q:" In "Delta ABC, AC=AB.`
(ii) p: A and B are two sets such that A `sube` B and B `sube` A.
q: A=B.
(iii) p: `Delta ABC` is equilateral.
q: `Delta ABC` is equiangular.
(iv) p: `{a in R" such that " | a | lt 2}.`
`q: {a in R" such that "(agt -2and alt 2)}.`

Explanation

We can combine the given statements as given below.
(i) In `Delta ABC, angleB = angleC hArr AC=AB.`
(ii) For any sets A and B, `A=B hArr(A sube B and B sube A).`
(iii) `A Delta ABC` is equilateral `hArr` its is equiangular.
(iv) For every real `a, |a|lt2 hArr (a gt-2 and a lt2).`