Given a question and a context passage, generate the answer having the word or phrase from the context passage. Here, the answer should be a shortest continous span from the passage.

Ex Input:
Context: The photo above represents water in three common states of matter. States of matter are different phases in which any given type of matter can exist. There are actually four well-known states of matter: solid, liquid, gas, and plasma. Plasma isnt represented in the iceberg photo, but the other three states of matter are. The iceberg itself consists of water in the solid state, and the lake consists of water in the liquid state. Q: Where is water in the gaseous state in the above photo? A: You cant see the gaseous water, but its there. It exists as water vapor in the air. Q: Water is one of the few substances that commonly exist on Earth in more than one state. Many other substances typically exist only in the solid, liquid, or gaseous state. Can you think of examples of matter that usually exists in just one of these three states? A: Just look around you and you will see many examples of matter that usually exists in the solid state. They include soil, rock, wood, metal, glass, and plastic. Examples of matter that usually exist in the liquid state include cooking oil, gasoline, and mercury, which is the only metal that commonly exists as a liquid. Examples of matter that usually exists in the gaseous state include oxygen and nitrogen, which are the chief gases in Earths atmosphere. A given kind of matter has the same chemical makeup and the same chemical properties regardless of its state. Thats because state of matter is a physical property. As a result, when matter changes state, it doesnt become a different kind of substance. For example, water is still water whether it exists as ice, liquid water, or water vapor. The most common states of matter on Earth are solids, liquids, and gases. How do these states of matter differ? Their properties are contrasted in the Figure 1.1. Click image to the left or use the URL below. URL: Properties of matter in different states. Q: The Figure 1.2 shows that a liquid takes the shape of its container. How could you demonstrate this? A: You could put the same volume of liquid in containers with different shapes. This is illustrated below with a beaker (left) and a graduated cylinder (right). The shape of the liquid in the beaker is short and wide like the beaker, while the shape of the liquid in the graduated cylinder is tall and narrow like that container, but each container holds the same volume of liquid. Q: How could you show that a gas spreads out to take the volume as well as the shape of its container? A: You could pump air into a bicycle tire. The tire would become firm all over as air molecules spread out to take the shape of the tire and also to occupy the entire volume of the tire. 
 Question: the only state in which matter has a fixed shape is

Ex Output:
solid.


Ex Input:
Context: Cells were first discovered in the mid-1600s. The cell theory came about some 200 years later. You can see a re- enactment of some of the discoveries that led to the cell theory in this video: MEDIA Click image to the left or use the URL below. URL: British scientist Robert Hooke first discovered cells in 1665. He was one of the earliest scientists to study living things under a microscope. He saw that cork was divided into many tiny compartments, like little rooms. (Do the cells in Figure 3.1 look like little rooms to you too?) Hooke called these little rooms cells. Cork comes from trees, so what Hooke observed was dead plant cells. In the late 1600s, Dutch scientist Anton van Leeuwenhoek made more powerful microscopes. He used them to observe cells of other organisms. For example, he saw human blood cells and bacterial cells. Over the next century, microscopes were improved and more cells were observed. By the early 1800s, scientists had seen cells in many different types of organisms. Every organism that was examined was found to consist of cells. From all these observations, German scientists Theodor Schwann and Matthias Schleiden drew two major conclusions about cells. They concluded that: cells are alive. all living things are made of cells. Around 1850, a German doctor named Rudolf Virchow was observing living cells under a microscope. As he was watching, one of the cells happened to divide. Figure 3.2 shows a cell dividing, like the cell observed by Virchow. This was an aha moment for Virchow. He realized that living cells produce new cells by dividing. This was evidence that cells arise from other cells. The work of Schwann, Schleiden, and Virchow led to the cell theory. This is one of the most important theories in life science. The cell theory can be summed up as follows: All organisms consist of one or more cells. Cells are alive and the site of all life processes. All cells come from pre-existing cells. All cells have certain parts in common. These parts include the cell membrane, cytoplasm, DNA, and ribosomes. The cell membrane is a thin coat of phospholipids that surrounds the cell. Its like the skin of the cell. It forms a physical boundary between the contents of the cell and the environment outside the cell. It also controls what enters and leaves the cell. The cell membrane is sometimes called the plasma membrane. Cytoplasm is the material inside the cell membrane. It includes a watery substance called cytosol. Besides water, cytosol contains enzymes and other substances. Cytoplasm also includes other cell structures suspended in the cytosol. DNA is a nucleic acid found in cells. It contains genetic instructions that cells need to make proteins. Ribosomes are structures in the cytoplasm where proteins are made. They consist of RNA and proteins. These four components are found in all cells. They are found in the cells of organisms as different as bacteria and people. How did all known organisms come to have such similar cells? The answer is evolution. The similarities show that all life on Earth evolved from a common ancestor. Besides the four parts listed above, many cells also have a nucleus. The nucleus of a cell is a structure enclosed by a membrane that contains most of the cells DNA. Cells are classified in two major groups based on whether or not they have a nucleus. The two groups are prokaryotic cells and eukaryotic cells. Prokaryotic cells are cells that lack a nucleus. The DNA in prokaryotic cells is in the cytoplasm, rather than enclosed within a nuclear membrane. All the organisms in the Bacteria and Archaea Domains have prokaryotic cells. No other organisms have this type of cell. Organisms with prokaryotic cells are called prokaryotes. They are all single-celled organisms. They were the first type of organisms to evolve. They are still the most numerous organisms today. You can see a model of a prokaryotic cell in Figure 3.3. The cell in the figure is a bacterium. Notice how it contains a cell membrane, cytoplasm, ribosomes, and several other structures. However, the cell lacks a nucleus. The cells DNA is circular. 
 Question: ______cell that lacks a nucleus

Ex Output:
prokaryotic cell


Ex Input:
Context: Brilliant but irresponsible scientist Tony Nelson (James Congdon) develops an electronic amplifier that he hopes will allow any object to achieve a 4th dimensional (4D) state. While in this state that object can pass freely through any other object. However, Tony failed to pay attention to the overload, which sparks an electrical fire that burns down his lab, resulting in the university terminating his contract. Now unemployed, Tony seeks out his brother Scott (Robert Lansing), a researcher working on a material called cargonite that is so dense as to be impenetrable, to help him with his experiment. Scott is underpaid and unappreciated at his job but does not have the drive to challenge his employer, Mr. Carson, for greater recognition, especially since Scott has been the driving force behind the development of cargonite (named after Carson, showing he is grabbing much of the credit for Scott's work). When his girlfriend (Lee Meriwether) falls for Tony, an enraged Scott steals Tony's experiment and starts playing with it, eventually sending himself into a 4D state. When demonstrating this to Tony, Scott does not turn on the amplifier power yet successfully passes his hand through a block of steel, meaning Scott can now enter the 4D state via his own will. Tony is amazed but warns Scott not to reveal this until he can further test it for any side effects. While in the 4D state, Scott can pass through any solid object. The downside is that, while in that state, Scott ages at a greatly accelerated rate. He soon learns how to survive however, when an aged Scott visits the company doctor, who, while examining him, suddenly drops dead. Simply by touching others, Scott can drain their lifeforce, thereby rejuvenating himself. One night, Scott experiments with his abilities by being able to shoplift a piece of fruit from a grocery store window. Scott also notices a diamond necklace on display in a jewelry store window, but decides against stealing it. However, when Scott sees the bank, his face breaks into a sly grin. The police are wondering about a bizarre crime, over $50,000 was stolen from the bank with no forced entry nor video footage of wrongdoing, and a $20 bill was found protruding from a piece of tempered steel. Tony realizes Scott is abusing his power and tries to convince the police of the experiment. Scott starts using his new found power to acquire all the things he felt he was denied: money, recognition, power, and women. Scott then confronts Mr. Carson, revealing the experiment, then taking his revenge "for the life drained from me" by literally draining Carson's life force to rejuvenate his. After killing Carson, Scott then proceeds to a sleazy bar. He gets some toughs to back down, and his new found bravado combined with his ill-gotten money to impress a bar girl. Later in a car, when they kiss, Scott does not kill her, but drains her life force to the point where she becomes old, frightening her into running away. The police have to find a way to stop a man who is practically unstoppable. Looking old now, Tony returns to the nuclear lab where they are also unable to stop him. The girlfriend catches him when he is solid and shoots and wounds Scott after they kiss (which does not drain her life force). Bleeding and feeling betrayed, Scott maniacally proclaims his invincibility and defiantly phases his body through a wall embedded with supposedly impenetrable cargonite, his hand, slowly and with seeming difficulty, phasing lastly through the wall. "The End" then appears on the screen. A moment later, a question mark appears turning the closing phrase into an interrogative statement leaving into question whether Scott has died or survived. 
 Question: What can Scott pass his hand through?

Ex Output:

a block of steel