I would have given them 100%! Each answer is absolutely grammatically correct, and funny too. The teacher had no sense of humour.
Q1. In which battle did Napoleon die?
* his last battle
Q2.. Where was the Declaration of Independence signed?
* at the bottom of the page
Q3.. River Ravi flows in which state?
Q4.. What is the main reason for divorce?
Q5.. What is the main reason for failure?
Q6.. What can you never eat for breakfast?
* Lunch & dinner
Q7.. What looks like half an apple?
* The other half
Q8.. If you throw a red stone into the blue sea what it will become?
Q9.. How can a man go eight days without sleeping ?
* No problem, he sleeps at night.
Q10. How can you lift an elephant with one hand?
* You will never find an elephant that has one hand.
Q11. If you had three apples and four oranges in one hand and four apples and three oranges in other hand, what would you have?
* Very large hands
Q12. If it took eight men ten hours to build a wall, how long would it take four men to build it?
*No time at all, the wall is already built.
Q13. How can you drop a raw egg onto a concrete floor without cracking it?
*Any way you want, concrete floors are very hard to crack.