Groundwater from 19 wells was classified as low or high in alkalinity and low or high in

Question:

Groundwater from 19 wells was classified as low or high in alkalinity and low or high in dissolved iron. There were 9 wells with high alkalinity, 7 that were high in iron, and 5 that were high in both.
(a) Based on these data, complete the following two-way frequency table.
(b) Calculate the relative frequencies of the cells.
(c) Calculate the relative frequencies separately for each row.