The Three Sons

Question: There is a farmer who has three sons. Nearing his death, he asked his three sons to find two objects that can fill the room he's in. The one who can deliver will be chosen as his heir. So the oldest son goes to the market to get hay while the middle son go get leaves. The youngest son goes to a shop and buys two things that he put in his pocket. The oldest son's hay only fills half the room, the middle son's leaves fills 2/4 quarters of the room, while the youngest fills the room with his two objects. Question: What are the two objects that the youngest son used to fill the room?

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Question: During what month do people sleep the least?

Question: When is 99 more than 100?

Question: What can be broken but never forgotten?

Question: Surrounded by life , yet life is its biggest enemy. But without life there is no need for it to exist. What is it?