A total station was used to observe B from A and then to observe A from B. The observations are as follows:
From To Zenith angle Slope distance Height of inst. Hight of target
A B 89°50'40" 425.830 1.52 1.60
B A 90°09'32" 425.836 1.68 1.60
If reduces level of A is 20.1xx m find the reduced level of B.
XX = Last two digits from your ID(e.g., ID 900172567 XX = 67)