2 For what values of parameters a b E R the operation x y xy ax by 2 defined for x y E R is commutative and associative 3 For G 1 3 5 9 and xoy defined as the last decimal digit of the number xy 3x 3y 4 i show that o is a well defined operation on G and present its table ii find the neutral element of o iii prove that G o is a group