i. * closed operation, x*y belongs to Z
ii. Associative
iii. x*e = x
x + e + 2 = x
e = -2 // identity element exists
iv. x*y=e
x+y+2 = -2
x+y=-4
y = (-4 -x) inverse exist
v. Commutative
Hence statement 1 is Abelian Group!
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Statement 2: Not Associative
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Statement 3.
x*y=x^{2}y^{2 }for x,y ∈ Z not associative not even semi group