The idea that Earth is a magnet is far from new. It was first proposed in 1600 by a British physician named William Gilbert. Knowing it acts like a magnet is one thing. Knowing why it acts like a magnet is more difficult. In fact, finding out why is a fairly recent discovery. To find out why required new technology. It was the seismograph that made it possible to learn why the Earth acted like a magnet. Seismograph are used to study earthquakes. By studying earthquake waves they were able to learn about Earths interior. They discovered that Earth has an inner and outer core. The outer core consists of liquid metals, mainly iron and nickel. Scientists think that Earths magnetic field is generated here. It is caused by the motion of this liquid metal. The liquid metal moves as Earth spins on its axis.

Question: "What do we know and don't about the Earth and magnets?"

Response: "There are always unanswered questions"
OPTIONS:
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A: yes

Have you ever seen an egg? Some animals do not have live births. Instead, they lay eggs. The eggs contain the embryo. The embryo matures in the egg. With time, it will hatch. Some animals hatch and do not need care from their parents. They are ready to live on their own. Other animals will still need the care of their parents. Sea turtles break out of their shells. They immediately walk to the ocean. They do this with no help from an adult. Birds stay in the nest for many weeks. They are cared for by their parents. They leave the nest when they are strong enough to fly. Some animals give birth to live offspring. Animals like horses, cows, and whales give live birth. Their offspring are born looking like mini adults.

Question: "How do young birds behave?"

Response: "They do this with no help from an adult"
OPTIONS:
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A: no

Mary loved walking through the woods with her dog, Max. Max and Mary would go on all sorts of adventures together. They really loved looking for blueberries together and then falling asleep next to each other in the tall grass. One day, as Mary was picking the blueberries, she turned around to find that Max was not there. She became worried and ran off to look for her dog. She looked in all of their favorite spots...next to the stream, in their secret hiding place behind the raspberry bushes, and even inside the old cabin that sat in the woods. But poor Max was nowhere to be found. Nonetheless, Mary would not give up. She kept looking and she found him not very far away. He had seen a squirrel and run to chase it. When Mary called Max's name he left the squirrel and happily returned to Mary, wagging his tail as he went.

Question: "What things did Mary do?"

Response: "Cooking"
OPTIONS:
- no
- yes

A:
no