To properly align the shaft of a base-mounted pump to the shaft of its driver (usually an electric motor), very thin shims must be placed under the mounting feet. You must report the total thickness of the shims placed under each foot. Shims are provided in precise thicknesses, measured in thousandths of an inch. In this case, three shims were placed under one foot. One shim is marked 0.030", the second is marked as 0.015", and the third is marked as 0.007". What is the total thickness of the three shims? Your answer should be to the nearest thousandth of an inch.