Answer:
PH is a scale used to specify the acidity or basicity of an aqueous solution.
Acid soils have a pH below 7
6.5 to 7.5 for basic soils
Answer:
Atoms are the most reactive when they have a full outer energy level.
Explanation:
Atoms are the least reactive and most stable when their outermost electron shell is full.
Option (a) has a greater chance of being the answer — the respiratory system does take in Oxygen to break down glucose into Carbon dioxide and water vapor, releasing energy.
