1. Very possibly the 2nd choice. All the others are rational. An irrational number has an infinite, non-repeating decimal portion.
2. √1/169 = (√1)/169 = 1/169. Perhaps you mean √(1/169).

. . . . corresponds to the 3rd choice
3. Square root both sides.
.. x = ±√98 ≈ 9.9, -9.9 . . . . . corresponds to the 3rd choice