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".

Q: Fossils can be used to match up rock layers. As organisms change over time, they look different. Older fossils will look different than younger fossils. Some organisms only survived for a short time before going extinct. Knowing what organisms looked like at certain times also helps date rock layers. Some fossils are better than others for this use. The fossils that are very distinct at certain times of Earths history are called index fossils. Index fossils are commonly used to match rock layers. You can see how this works in Figure 2.30. If two rock layers have the same index fossils, then they're probably about the same age. <sep>What kind of fossils are used to date rock layers?<sep>Index fossils

A: Yes
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Q: Magnets are able to place a force on certain materials. This force is called a magnetic force. The force a magnet exerts is a little different from the forces you may normally think about. You exert a force on a book when you lift it. You also exert a force on the pedals of your bicycle. In both those cases, those forces cause a change. The change you see in both these cases is called motion. Magnets, too, can produce change. They can produce motion just like you do. Unlike you, magnets do not have to touch something to exert a force. A magnetic force is exerted over a distance. Thats right, a magnet can push or pull certain items without ever touching them. Thats how the maglev train works. Do you know another type of force that does not require objects to touch? These forces are known as non-contact forces. Another type of non-contact force you may be familiar with is gravity. Gravity too can cause changes in motion. Gravity holds our moon in orbit without touching it. <sep>The force magnets put on certain materials is called what?<sep>Magnets do not put force on certain materials

A: No
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Q: The protagonist Preetam ( ( ( Ganesh , on a visit to Eva Mall amidst a heavy wind , spots a pretty girl , Nandini . While staring at her , he inadvertently falls into a manhole . Nandini rescues him from the pit , but in the process loses her heart-shaped watch she had just bought . While accompanying his mother to Madikeri , Preetam confronts a man named Jaanu . Jaanu , who has been following Nandini , beats up Preetam thinking that he is in love with Nandini . Preetam , unaware that Jaanu has vowed not to allow any one near Nandini , trashes Jaanu and his gang in return . In Madikeri , Preetam meets Nandini unexpectedly . He identifies himself and expresses his love towards her and offers to tie the watch as an indication for their marriage . Nandini , who is already engaged rejects his request . Still , Preetam vows to marry Nandini if she meets him again . In the meantime , Preetam discovers that his host in Madikeri , Col. Subbayya is Nandini's father , who is pretty much deaf , and Nandini's marriage is a just a week away . Dejected , Preetam throws Nandini's heart-shaped watch away . But Nandini calls him over the phone and taunts him to return . Delighted , Preetam goes in search of her watch and brings it back . While searching it , he spots a rabbit , Which he calls Devadas , and brings it along with him . Since Nandini's friends are due to arrive from Mumbai for the marriage , Preetam takes Nandini to the railway station . The train from Mumbai is delayed by five hours , so Nandini and Preetam decide to visit a nearby hill-temple . <sep>Who did Preetam confront that had also been following Nandini?<sep>Devadas

A:
No
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