One of the reactions you observed resulted in this product: nacl + h2o + co2 (g)? what well did this reaction occur in? describe how the observations for this reaction support your answer.

Chemical reaction: NaHCO₃ + HCl → NaCl + CO₂ + HCl.
Reaction occurs between sodium bicarbonate (sodium hydrogen carbonate) and hydrochloric acid. For example, hydrogen carbonate mixed with water is used like antacid (neutralizes stomach acidity), contverts stomach acid (hydrochloric acid) to carbon dioxide.

Most likely a is the answer - because  you generate   38 atp's but also consume an atp.   each atp gives approx. less than 4 kcal so probably a is the closest answer.