instruction:
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.
question:
Context: A covalent bond is the force of attraction that holds together two atoms that share a pair of electrons. The shared electrons are attracted to the nuclei of both atoms. Covalent bonds form only between atoms of nonmetals. The two atoms may be the same or different elements. If the bonds form between atoms of different elements, a covalent compound forms. Covalent compounds are described in detail later in the lesson. To see a video about covalent bonding, go to this URL: (6:20). MEDIA Click image to the left or use the URL below. URL: Figure 7.7 shows an example of a covalent bond forming between two atoms of the same element, in this case two atoms of hydrogen. The two atoms share a pair of electrons. Hydrogen normally occurs in two-atom, or diatomic, molecules like this (di- means "two"). Several other elements also normally occur as diatomic molecules: nitrogen, oxygen, and all but one of the halogens (fluorine, chlorine, bromine, and iodine). Covalent bonds form because they give atoms a more stable arrangement of electrons. Look at the hydrogen atoms in Figure 7.7. Alone, each hydrogen atom has just one electron. By sharing electrons with another hydrogen atom, it has two electrons: its own and the one in the other hydrogen atom. The shared electrons are attracted to both hydrogen nuclei. This force of attraction holds the two atoms together as a molecule of hydrogen. Some atoms need to share more than one pair of electrons to have a full outer energy level. For example, an oxygen atom has six valence electrons. It needs two more electrons to fill its outer energy level. Therefore, it must form two covalent bonds. This can happen in many different ways. One way is shown in Figure 7.8. The oxygen atom in the figure has covalent bonds with two hydrogen atoms. This forms the covalent compound water. In some covalent bonds, electrons are not shared equally between the two atoms. These are called polar bonds. Figure 7.9 shows this for water. The oxygen atom attracts the shared electrons more strongly because its nucleus has more positively charged protons. As a result, the oxygen atom becomes slightly negative in charge. The hydrogen atoms attract the electrons less strongly. They become slightly positive in charge. For another example of polar bonds, see the video at this URL: (0:52). MEDIA Click image to the left or use the URL below. URL: In other covalent bonds, electrons are shared equally. These bonds are called nonpolar bonds. Neither atom attracts the shared electrons more strongly. As a result, the atoms remain neutral. Figure 7.10 shows an example of nonpolar bonds. Covalent bonds between atoms of different elements form covalent compounds. The smallest, simplest covalent compounds have molecules with just two atoms. An example is hydrogen chloride (HCl). It consists of one hydrogen atom and one chlorine atom. The largest, most complex covalent molecules have thousands of atoms. Examples include proteins and carbohydrates. These are compounds in living things. Helpful Hints Naming Covalent Compounds Follow these rules in naming simple covalent compounds: The element closer to the left of the periodic table is named first. The second element gets the suffix ide. Prefixes such as di- (2) and tri- (3) show the number of each atom in the compound. These are written with subscripts in the chemical formula. Example: The gas that consists of one carbon atom and two oxygen atoms is named carbon dioxide. Its chemical formula is CO2 . You Try It! Problem: What is the name of the compound that contains three oxygen atoms and two nitrogen atoms? What is its chemical formula? Covalent compounds have different properties than ionic compounds because of their bonds. Covalent compounds exist as individual molecules rather than crystals. It takes less energy for individual molecules than ions in a crystal to pull apart. As a result, covalent compounds have lower melting and boiling points than ionic compounds. Many are gases or liquids at room temperature. Covalent compounds have shared electrons. These are not free to move like the transferred electrons of ionic 
 Question: any compound consisting of two or more nonmetals
answer:
covalent compound


question:
Context: To investigate whether gender is an independent factor associated with disease expression in early rheumatoid arthritis (RA) patients. 438 patients with early RA (disease duration less than one year) were studied. They all were patients with early RA who presented at the Rheumatology Clinic of the University Hospital of Ioannina during the period 1991-2000. All patients fulfilled the American College of Rheumatology criteria for RA. The demographic, clinical, laboratory, radiological and therapeutic characteristics of the disease at diagnosis, and at the last follow-up were analyzed according to gender. We studied 312 women and 126 men with early RA. The female to male ratio was 2.5:1 and the mean age at diagnosis was 49.4 +/- 14.9 years for women and 55.3 +/-15.6 years for men (P < 0.0003). Women had a longer duration of follow-up (P < 0.0003). There were no differences between genders in the general symptoms or the simmetricity of joint involvement at at disease onset. However at disease onset women had a higher erythrocyte sedimentation rate (ESR) (> 30 mm/1st hour), although there were no significant differences between the two groups concerninig the rest of the clinical, laboratory and radiological findings. At the last follow-up women still had a higher ESR (>30 min/1st hour), but no significant differences were found between the two groups concerning the rest of the parameters investigated independently of the follow-up duration. Finally, women and men showed the same degree of radiological changes and functional ability and were treated similarly except for the more frequent use of hydroxychloroquine in women. It seems that gender does not signficantly influence the expression of RA. 
 Question: Is Rheumatoid Arthritis more common in men or women?
answer:
women


question:
Context: When once-wealthy string magnate Rudolf Smuntz (William Hickey) dies, he leaves his outdated string factory and a run-down mansion to his two sons, Lars (Lee Evans) and Ernie (Nathan Lane). When Lars refuses a proposal by representatives from the large Zeppco conglomerate to purchase their string factory, his wife April (Vicki Lewis) throws him out. Meanwhile, Ernie serves Mayor McKrinkle (Cliff Emmich) at his restaurant in anticipation of becoming a famous chef for serving such a high-profile guest. However, the mayor is poisoned by a cockroach (which came from Rudolf's old box of Cuban cigars that Ernie took for himself) and suffers two heart attacks, with the latter fatal. As a result, Ernie's restaurant is closed down by the Board of Health. Finding blueprints of the mansion that they decide to live in, Ernie and Lars discover that it is a lost masterpiece designed by famous architect Charles Lyle LaRue. LaRue collector Alexander Falko (Maury Chaykin) makes a proposal, but Ernie refuses under the belief they can make a larger profit by restoration and auction. However, the brothers have already realized that the house has one stubborn occupant: a tiny and treacherous mouse. When a single mousetrap proved to be useless against the mouse, Ernie and Lars cover the entire kitchen floor with a number of mousetraps, but end up trapped in the kitchen when the door is locked. The mouse slips through the maze of traps with ease and drops a cherry, setting off the mousetraps in a dominoes effect. The brothers attempt to kill the mouse with a vacuum cleaner, but are covered with sewage. The brothers purchase a monstrous cat named "Catzilla" to deal with the mouse. Catzilla chases the mouse throughout the house while destroying everything, but gets tricked onto the house's dumbwaiter as the mouse sends him on a one-way trip down to his demise. They then hire an eccentric exterminator named Caesar (Christopher Walken) to handle the mouse, though he is severely injured and hospitalized. Later, Ernie chases the mouse up a chimney and gets stuck, and Lars attempts to light a match while the mouse starts a gas leak, creating an explosion that blasts Ernie out of the chimney and into the lake. Ernie takes a shotgun to fire at the mouse, accidentally shooting a compressed can of pesticide that Caesar left behind, making a large hole. After the two recover, Lars throws an orange at Ernie, but accidentally knocks the mouse unconscious. Unable to finish him off, they instead seal the mouse in a box and mail him to Fidel Castro in Cuba. The brothers reconcile again and finish renovating the house. When the night of the auction arrives, Lars discovers the mouse's box in the snow returned due to insufficient postage and with a big hole gnawed through it. Lars and Ernie panic upon seeing the mouse return, but attempt to maintain their composure as the auction continues. The mouse also devours Rudolf's "lucky string," which he gave to the brothers before his death, making their vendetta even more personal. The brothers desperately attempt to flush out the mouse by feeding a hose into the wall. As the auction reaches a record $25 million bid, the house rapidly floods through the walls and the floors, causing everyone to be washed out of the house as it promptly collapses. The brothers' only consolation is the fact that the mouse must finally be dead as their father's "lucky string" is found in the wreckage. With nowhere else to go, the brothers return to the factory and fall asleep, with only a single chunk of cheese for food. Having followed them, the mouse restarts and feeds the cheese into the machinery inventing the world's first string cheese, which inspires Ernie and Lars. Ernie and Lars end their war with the mouse and have successfully rebuilt the factory as a novelty string cheese company. Lars has begun a relationship with one of the two sisters Hilde, and Ernie puts his culinary skill to work in developing new cheese flavors with the mouse as his personal taste-tester. 
 Question: Who does Ernie accidentally kill?
answer:

the mayor