D. Sodium hydroxide aka naOH
Its a Reflector
Reflector is some sort of material that is used to collect or bounce off energy such as sound, light, or radio wave
Usually it took form in some sort of parabolic that revolve around an axis
I have provided the steps and solution within the attachment. The pH of the solution would be 12.30, this indicates that the solution is basic, as a higher value of pH indicates presence of more hydroxide ions and less of hydrogen ions in the solution.
In the Southern Hemisphere this would be around June 20 and culminates on September 22.
Answer:

Explanation:
Hello!
In this case, according to the chemical reaction by which HBr reacts with Ba(OH)2:

We can see there is a 2:1 mole ratio between the acid and the base; thus, at the equivalent point we can write:

Therefore, for is to compute the volume of the used base, we proceed as shown below:

And we plug in to obtain:

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