Answer:
the amount of some item in the water.
Step-by-step explanation:
The full meaning for TDS is Total Dissolved Solids. That is, it is ised for measuring the total amount of solids dissolved in a solvent
The unit of TDS can be milligrams per liter(mg/l) or part per million (ppm)
We can therefore, conclude that TDS and ppm are used to measure the amount of some items in the water