<span>The best reason I can think of for why we believe that air is a mixture is that freezing air slowly yields different liquids at different temperatures. Liquid nitrogen has a different boiling point than liquid oxygen. They also freeze at different temperatures. If air were only 1 compound, then air in its entirety would have a single boiling point and a single freezing point. </span>
A size dependent property is a physical property that changes when the size of an object changes.
<u>Answer:</u> The mass of chlorine needed by the plant per day is 
<u>Explanation:</u>
We are given:
Volume o water treated per day = 25,000,000 gallons
Converting this volume from gallons to liters, we use the conversion factor:
1 gallon = 3.785 L
So, 
Amount of chlorine applied for disinfection = 10 mg/L
Applying unitary method:
For 1 L of water, the amount of chlorine applied is 10 mg
So, for
of water, the amount of chlorine applied will be 
Hence, the mass of chlorine needed by the plant per day is 
In response of what like what’s the full clear question