Answer/Explanation:
We cannot see the passage, but SAD stands for Seasonal Affective Disorder. SAD is a type of depressive disorder related to lack of light, and therefore changes with the seasons. It is a severe version of the "winter blues"
In the winter months, where the days are shorter, individuals who suffer from SAD suffer from mood changes. They get depressed, have a reduction in energy levels, and withdraw socially. They may also gain weight. This causes problems with relationships, work, and school.
Since SAD is linked to light, SAD is likely more common in the Northern areas of the United States, where winter days are shorter.
The balanced equation :
2NaHCO₃⇒CO₂ + Na₂CO₃+H₂O
<h3>Further explanation</h3>
Given
Reaction
NaHCO(s) --> _CO2+_NaCO(s)+_H2O
Required
The balanced equation
Solution
Maybe the equation should be like this :
NaHCO₃⇒CO₂ + Na₂CO₃+H₂O
Give a coefficient
NaHCO₃⇒aCO₂ + bNa₂CO₃+cH₂O
Make an equation
Na, left=1, right=2b⇒2b=1⇒b=1/2
H, left=1, right=2c⇒2c=1⇒c=1/2
C, left=1, right=a+b⇒a+b=1⇒a+1/2=1⇒a=1/2
The equation becomes :
NaHCO₃⇒1/2CO₂ +1/2Na₂CO₃+1/2H₂O x2
2NaHCO₃⇒CO₂ + Na₂CO₃+H₂O
It is too early for students to have career preferences while still in school
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