Read the statement and answer:
1.
Sheela made a circuit by connecting the positive terminal of the battery to the LED's shorter lead and leaving the negative terminal of the battery in the water bottle. As a result, the lamp does not glow. What is the reason for this?
2.
Asha built a circuit by pouring water into a glass jar and inserting two carbon electrodes. She poured vinegar into the water and stirred it in. The reason behind it is
3.
When Shivu is experimenting with potato, he found a bluish-green spot on the potato around the copper wire connected to the one terminal of the battery, whereas no such spot occurs at