Answer:
i. {n E Z: n is even} can be written as: {..., -4, -2, 0, 2, 4, ...}
ii. {n^2: n E N} can be written as: {0, 1, 4, 9, 16, 25, ...}
iii. < 4 can be written as: {-3, -2, -1, 0, 1, 2, 3}
iv. {x E Z: x^2 - 1 = 0} can be written as: {-1, 1}
v. {x E Q: x^2 - 2 = 0} can be written as: {-√2, √2}
vi. {x E R: x^2 - 2 = 0} can be written as: {-√2, √2}