How would I figure the following problems out?

TRUE OR FALSE:
1.
[(z - 2)^2/(3z^2)] / [(z - 2)/(6z)] = [2(z + 2)]/z => FALSE
[(z - 2)^2/(3z^2)] / [(z - 2)/(6z)] = [2(z - 2)]/z => TRUE
2.
(9y)/(3x) - (6y)/(3x) = y/x => TRUE
MULTIPLE CHOICE:
2y/9 + y/3 =
5y/9
Answer choice:
A. 5y/9

1.
[(z - 2)² / 3z²] ÷ [(z - 2) / 6z]
= [(z - 2)² / 3z²] × [6z / (z - 2)]
= 6z(z - 2)² / [3z²(z - 2)]
= 2(z - 2) / z
Then, it is FALSE.


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2.
(9y / 3x) - (6y / 3x)
= (9y - 6y) / 3x
= 3y / 3x
= y/x
Then, it is TRUE.


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MULTIPLE CHOICE:
1.
(2y/9) + (y/3)
= (2y/9) + (3y/9)
= (2y + 3y)/9
= 5y/9

..... The answer is : A. 5y/9

1.)
(z-2)^2/3z^2 divided by z-2/6z is equal to 2(z+2)/z.
Or,
(z-2)^2/3z^2 / (z-2)/6z = (z-2)(6z/3z^2) = 2(z+2)/z. .. . . . Correct

2.)
9y/3x - 6y/3x is equal to y/x.
So,
(9y - 6y) / 3x = 3y/3x = y/x. ..... Correct.