I believe the answer is: <span>Binocular Disparity
</span><span>Binocular Disparity happens when the right and left eyes perceive a same object differently from one another, which create a horizontal defect in the victim's vision. This condition is most commonly caused by retinal damage during injuries/accidents.
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The skill to do this is called <span>Discriminating
You discriminate one object from another, which is why it is said that someone can have discriminating taste if they're good at telling similar things apart.</span>
The concrete operational stage
HVAC, which stands for Heating, Ventilation and Air Conditioning, is very useful in countries with 4 seasons. During summer, they use air conditioning; during winter, they use heat pumps. The capacity of HVACs are usually expressed in tons. 1 ton is equal to 12,000 BTU/h. For residential heating systems, the capacity usually ranges from 1-5 tons.
