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.

Question: "How do astronauts hear each other?"

Answer: "Boyle carries them with his empty jar."

Response: no

Joey got a German Shepherd for his birthday present. He had never had any pets before, but was always excited to see the other dogs and cats in his neighborhood. Since his birthday was in June, he spent a lot of time playing outside with his new puppy, which he named Max. Max and Joey would often run through fields in a game of chase. They also liked to go through the small forest behind the house, making a game of hide and seek. They never went near the lake because Joey was afraid of water. One day, Max hid a little too well and Joey couldn't find him. Joey spent the afternoon looking for his German Shepherd where they often played, like the field and forest. Joey was a shy boy who often read by himself, and Max was his best friend. After dinner, he went to look for Max one last time before he had to take a bath and go to bed. He heard some barking on the next street, so he ran to see if it was his puppy. Sure enough, he saw Max playing with a poodle. The dogs were having so much fun. Joey brought Max home, happy that he had his puppy back. Max seemed to be happy to have his human by his side as well as a new doggy friend. All summer long, Joey took Max to the poodle's house so they could play without having to worry about losing his present.

Question: "What two games did Max and Joey play?"

Answer: "Chase and hide and seek"

Response: yes

What if you could drain all of Earths oceans? What would it look like? You might be really surprised. You see that the surface has two main features. It has continents and ocean basins. Continents are large land areas. These are the areas that are mostly above sea level. Ocean basins extend from the edges of continents. They include the ocean floor and Earths deep ocean trenches. You will also notice the ocean floor is not flat. It too has many Continents are much older than ocean basins. Some rocks on the continents are billions of years old. Ocean basins may only be millions of years old. Because the continents are so old, a lot has happened to them! As we view the land around us, we see landforms. Landforms are physical features on Earths surface. These features change over time, but how? There are actually two types of forces at work.

Question: "What does the Earth's surface consist of?"

Answer: "Two main features - Continents and Ocean Basins"

Response: yes

The explosion, while killing one of the Cossacks and seriously wounding the driver and people on the sidewalk, had only damaged the bulletproof carriage, a gift from Napoleon III of France. The emperor emerged shaken but unhurt. Rysakov was captured almost immediately. Police Chief Dvorzhitsky heard Rysakov shout out to someone else in the gathering crowd. The surrounding guards and the Cossacks urged the emperor to leave the area at once rather than being shown the site of the explosion. Nevertheless, a second young member of the Narodnaya Volya, Ignacy Hryniewiecki, standing by the canal fence, raised both arms and threw something at the emperor's feet. He was alleged to have shouted, "It is too early to thank God". Dvorzhitsky was later to write:

Question: "What happened to Rysakov that caused him to shout out to someone else in the gathering crowd?"

Answer: "He was captured"

Response:
yes