Awater treatment plant needs to maintain the ph of the water in the reservoir at a certain level. to monitor this, they take 2 oz. of water at 37 locations every hour, measure the ph at each of those locations, and find their average. if the ph level of the reservoir is ok, the results at each location will have varying results, with an average ph of 8.5 and a standard deviation of 0.22.

explanation:

on disadvantage of hydroelectric power is the cost. another disadvantage of using hydroelectric power is finding a water source powerful enough to harvest hydroelectric power.

im not intirely sure but i think the anwser is d relative humidity

there are no options but this may your question,

leaves enable photosynthesis to occur. photosynthesis is the process by which leaves absorb light and carbon dioxide to produce glucose (food) for plants to grow. leaves are adapted to perform their function, eg they have a large surface area to absorb sunlight.

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