Below is the partially completed multiplication table of a group G={p,q,r,s,t,u} i) Which element of G is the identity? Explain your reasoning. ii) What is the inverse of q ? Explain your reasoning. iii) Calculate p(rq) and hence find pr. iv) Complete the table, given that G is abelian, that G has an element of order 2 and that the inverse of p is u. [4].