Answer the following:
 
After attending a birthday party, Janani complained of a burning sensation in her stomach. Her mother suspected that excess acid in the stomach was responsible for the discomfort. She gave Ananya a medicine prescribed by the doctor to relieve the condition.
 
i. The discomfort is caused due to excess ________ in the stomach.
 
ii. The medicine given to Ananya is likely to be ________ in nature.
 
iii. Which of the following substances is commonly present in an antacid?
 
iv. The doctor prescribes an antacid. Why does the antacid help Janani?