Answer
See below.
Work Step by Step
$\text{z-score}=\frac{\text{data item-mean}}{\text{standard deviation}}$
Hence here the z-scores: $z_1=\frac{128-100}{16}=1.75,z_2=\frac{127-100}{15}=1.8$, thus the person doing the Wechsler test has a higher score.
