In this task, you will be presented with a context passage, a question about that paragraph, and a possible answer to that question. The task is to check the validity of the answer. Answer with "Yes" or "No".
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Question: Sound waves are mechanical waves. They can travel only through matter. They cannot travel through empty space. This was demonstrated in the 1600s by a scientist named Robert Boyle. Boyle placed a ticking clock in a sealed glass jar. The clock could be heard ticking through the air and glass of the jar. Then Boyle pumped the air out of the jar. The clock was still running, but the ticking could not be heard. Thats because the sound couldnt travel without air particles to transfer the sound energy. Is there any other place where sound cannot be heard? Here is a hint: is there any other place that does not have air molecules? Thats right, in space sound cannot be transferred. So can astronauts hear each other? Yes, they can, because they are in enclosed space stations or pressurized suits.In both cases, they are surrounded by air molecules. If they left their space ship and did not use their electronics, they would not be able to hear each other. Next time you watch a science fiction movie, think about this factoid. When spaceships are destroyed by hostile alien beings, there would be no sound heard. Sound waves can travel through many kinds of matter. <sep>Can sound waves travel through empty space?<sep>definitely not

Answer: Yes

Question: When you get sick, your body springs to action. Your body starts to fight the illness. Thats why you want to eat right and get plenty of sleep. You need a strong immune system to fight off illness. Plants dont have an immune system. That does not mean they do not get sick. Plants are affected by disease just like us. Typically, their first line of defense is the death of part of the plant. This prevents the infection from spreading. Many plants also produce special chemicals to fight disease. For example, willow trees produce a chemical to kill the bacteria. The same compound is used in many acne products. You can see a picture of a willow tree in Figure Plants may be smarter than we think. No, they cannot talk to each other. They may be able to send messages, though. <sep>What do humans have that plants don't have?<sep>Immune systems

Answer: Yes

Question: The day was just breaking, as I left the tower; though it was still too dark in the house to be able to see without a light, and I took one of the study candles with me on my 'round. By the time I had finished the ground floor, the daylight was creeping in, wanly, through the barred windows. My search had shown me nothing fresh. Everything appeared to be in order, and I was on the point of extinguishing my candle, when the thought suggested itself to me to have another glance 'round the cellars. I had not, if I remember rightly, been into them since my hasty search on the evening of the attack. For, perhaps, the half of a minute, I hesitated. I would have been very willing to forego the task--as, indeed, I am inclined to think any man well might--for of all the great, awe-inspiring rooms in this house, the cellars are the hugest and weirdest. Great, gloomy caverns of places, unlit by any ray of daylight. Yet, I would not shirk the work. I felt that to do so would smack of sheer cowardice. Besides, as I reassured myself, the cellars were really the most unlikely places in which to come across anything dangerous; considering that they can be entered, only through a heavy oaken door, the key of which, I carry always on my person. <sep>Why search the cellar?<sep>He hadn't been there since the evening of the attack

Answer:
Yes