Pick up the correct statement from the following?
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A. Manhole covers are made circular for the convenience of the cleaning staff
C. The boning rod is used for checking the levels of the sewer inverts
D. A manhole is classified as shallow manhole if its depth is less than 0.9 m
Found an error? Read our corrections policy and submit a sourced correction below. You can also share a useful explanation in your own words.