One square grid cell is 7 m on each side. Four corner cut depths, all positive downward from existing ground to the design plane, are 0.3, 0.5, 0.7, 0.9 m. For this exercise volume equals cell area times the mean of its four corner depths. A second cell of the same area has uniform cut depth 0.4 m. No bulking or compaction is included.
Calculate the area of one cell in m². Keep intermediate values unrounded; round the final result to four decimal places if necessary.
