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.

Input: Consider Input: Context: When you take a walk along a beach, what do you find there? Sand, the ocean, lots of sunlight. You may also find shells. The shells you find are most likely left by organisms in the phylum Mollusca. On the beach, you can find the shells of many different mollusks ( Figure 1.1), including clams, mussels, scallops, oysters, and snails. Mollusks are invertebrates that usually have a hard shell, a mantle, and a radula. Their glossy pearls, mother of pearl, and abalone shells are like pieces of jewelry. Some mollusks, such as squid and octopus, do not have shells. The Mollusks body is often divided into different parts ( Figure 1.2): On the beach, you can find a wide variety of mollusk shells. 1. A head with eyes or tentacles. 2. In most species, a muscular foot, which helps the mollusk move. Some mollusks use the foot for burrowing into the sand, and others use it for jet-propulsion. 3. A mantle, or fold of the outer skin lining the shell. The mantle often releases calcium carbonate, which creates an external shell, just like the ones you find on the beach. The shell is made of chitin, a tough, semitransparent substance. 4. A mass housing the organs. 5. A complete digestive tract that begins at the mouth and runs to the anus. 6. Most ocean mollusks have a gill or gills to absorb oxygen from the water. 7. Many species have a feeding structure, the radula, found only in mollusks. The radula can be thought of as a "tongue-like" structure. The radula is made mostly of chitin. Types of radulae range from structures used to scrape algae off of rocks to the beaks of squid and octopuses. This is the basic body plan of a mollusk. Note the mantle, gills, and radula. Keep in mind the basic body plan can differ slightly among the mollusks. Mollusks are probably most closely related to organisms in the phylum Annelida, also known as segmented worms. This phylum includes the earthworm and leech. Scientists believe these two groups are related because, when they are in the early stage of development, they look very similar. Mollusks also share features of their organ systems with segmented worms. Unlike segmented worms, however, mollusks do not have body segmentation. The basic mollusk body shape is usually quite different as well. 
 Question: the foot of a squid is probably used for

Output: jet-propulsion.


Input: Consider Input: Context: The U.S. Census for 2010 reported 332,199 households in Indianapolis, with an average household size of 2.42 and an average family size of 3.08. Of the total households, 59.3% were family households, with 28.2% of these including the familys own children under the age of 18; 36.5% were husband-wife families; 17.2% had a female householder (with no husband present) and 5.6% had a male householder (with no wife present). The remaining 40.7% were non-family households. , 32% of the non-family households included individuals living alone, 8.3% of these households included individuals age 65 years of age or older. 
 Question: Which group from the census is smaller: family households or non-family households?

Output: non-family households


Input: Consider Input: Context: Halogens are highly reactive nonmetallic elements in group 17 of the periodic table. As you can see in the periodic table 1.1, the halogens include the elements fluorine (F), chlorine (Cl), bromine (Br), iodine (I), and astatine (At). All of them are relatively common on Earth except for astatine. Astatine is radioactive and rapidly decays to other, more stable elements. As a result, it is one of the least common elements on Earth. Q: Based on their position in the periodic table from the Figure 1.1, how many valence electrons do you think halogens have? A: The number of valence electrons starts at one for elements in group 1. It then increases by one from left to right across each period (row) of the periodic table for groups 1-2 and 13-18 (numbered 3-0 in the periodic table above.) Therefore, halogens have seven valence electrons. The halogens are among the most reactive of all elements, although reactivity declines from the top to the bottom of the halogen group. Because all halogens have seven valence electrons, they are eager to gain one more electron. Doing so gives them a full outer energy level, which is the most stable arrangement of electrons. Halogens often combine with alkali metals in group 1 of the periodic table. Alkali metals have just one valence electron, which they are equally eager to donate. Reactions involving halogens, especially halogens near the top of the group, may be explosive. You can see some examples in the video below. (Warning: Dont try any of these reactions at home!) Click image to the left or use the URL below. URL: The halogen group is quite diverse. It includes elements that occur in three different states of matter at room temperature. Fluorine and chlorine are gases, bromine is a liquid, and iodine and astatine are solids. Halogens also vary in color, as you can see in the Figure 1.2. Fluorine and chlorine are green, bromine is red, and iodine and astatine are nearly black. Like other nonmetals, halogens cannot conduct electricity or heat. Compared with most other elements, halogens have relatively low melting and boiling points. Most halogens have a variety of important uses. A few are described in the Figure 1.3. Q: Can you relate some of these uses of halogens to the properties of these elements? A: The ability of halogens to kill germs and bleach clothes relates to their highly reactive nature. 
 Question: halogens tend to form compounds with elements in group


Output: 1.