Using your knowledge of m/v = g/mL, you can start by putting that in the equation as:

And you know that the volume is 25 mL. So you could put this into the equation as:

And you also know that the molar mass of KCl is 74.55g (K = 39.1 g/mol and Cl = 35.45 g/mol. Add them together to get 74.55g/mol).
We can then put this in the equation as:

Then, we can mulitply them all together:

And now we know that
there are 0.01 moles of KCl in the sample.
Epithelial cells is the type of tissue that is designed to regulate temperature, secrete lubricants, and protect the body from harmful substances. Hope this helped! :)
Initially, I was going to say exhaustion, however with further research, I found that the first stage would be alarm. So your answer is:
<span>The first stage of the body‘s reaction to stress is known as the alarm stage
A. alarm
I hope this helped you, have a nice day
~ Karma
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