Answer:
1. the boy got bad smell from the opened packet left on the table due to rancidity.
2. the packet which was kept in the refrigerator did not have bad smell because they did not come in contact with oxygen.
Explanation:
rancidity - when fats and oils are oxidised they become rancid and their smell and taste changes.
when eatbles come in contact with oxygen they oxidised due to this we get bad smell and taste from it .
