A network of differential levels is run from existing benchmark Juniper through new stations A and B

Question:

A network of differential levels is run from existing benchmark Juniper through new stations A and B to existing benchmarks Red and Rock as shown in the accompanying figure. The elevations of Juniper, Red, and Rock are 685.65 ft, 696.75 ft, and 705.27 ft, respectively. Develop the observation equations for adjusting this network by least squares, using the following elevation differences?