Answer
The z-scores are -1.75 and 1.75.
Work Step by Step
The middle 92% goes from the 4th percentile to the 96th percentile.
The area of the standard normal deviation to the left of the 4th percentile is equal to 0.04.
According to Table V, the z-score which gives the closest value to 0.04 is -1.75.
Due to the symmetry (both standard normal distribution and the middle 92% are symmetric), the z-score for the 96th percentile is 1.75.
