An observation plane takes a photo of a building from a height of 1200m. above the ground and the height of the building is 99.78m. If the top of building is located 54.50mm. from the principal point, compute for the relief displacement.
\[
d = \frac{r h}{H}
\]
\[
d = \frac{(54.50mm.) (99.78m.)}{1200m.}
\]
\[
d = 4.531675mm.
\]
\[
h \approx 4.53mm. \leftarrow \text{answer}
\]