A 100` diameter by 35` high water-storage tank is being erected according to AWWA Standard D100. The maximum out of plumb distance for the top of the shell relative to the bottom of the shell shall be determined using what ratio?

A 100` diameter by 35` high water-storage tank is being erected according to AWWA Standard D100. The maximum out of plumb distance for the top of the shell relative to the bottom of the shell shall be determined using what ratio?