What is the relationship between groundwater and surface water? A Surface water percolates through the soil to form groundwater. B There is no relationship between surface and groundwater; they form independently. C Groundwater filters through the soil to form surface water. D Surface water is found in lakes directly above underground water sources.

The content of manganese (mn) in steel was determined spectrophotometrically and with the use of the standard addition method. an unknown sample of mn from a digested steel sample gave an absorbance of 0.185 when analyzed spectrophotometrically. when 5.00 ml of solution containing 95.5 ppm mn was added to 50.0 ml of the unknown steel solution (digested sample), the absorbance was 0.248. calculate the concentration, in parts-per-million (ppm), of mn in the digested steel sample solution.