Q: Q: Bread has little holes in it from carbon dioxide produced by what? Read this paragraph and choose the correct option from the provided answers: Bread has little holes in it from carbon dioxide produced by yeast. Choices: - sugar - water - bacteria - yeast A:
A: yeast

Q: Q: What happens to the density of air as the altitude decreases? Read this paragraph and choose the correct option from the provided answers: The pressure of the earth's atmosphere, as with any fluid, increases with the height of the column of air. In the case of earth's atmosphere, there are some complications. The density of the air is not uniform but decreases with altitude. Additionally there is no distinct top surface from which height can be measured. We can, however, calculate the approximate difference in pressure between two altitudes using the equation . The average pressure of the atmosphere at sea level is 1.013 10 5 Pa. This pressure is often expressed as 101.3 kPa. Choices: - multiplies - remains the same - increases - decreases A:
A: decreases

Q: Q: Liquids that mix with water in all proportions are usually polar substances or substances that form these? Read this paragraph and choose the correct option from the provided answers: Liquids that mix with water in all proportions are usually polar substances or substances that form hydrogen bonds. For such liquids, the dipole-dipole attractions (or hydrogen bonding) of the solute molecules with the solvent molecules are at least as strong as those between molecules in the pure solute or in the pure solvent. Hence, the two kinds of molecules mix easily. Likewise, nonpolar liquids are miscible with each other because there is no appreciable difference in the strengths of solute-solute, solvent-solvent, and solute-solvent intermolecular attractions. The solubility of polar molecules in polar solvents and of nonpolar molecules in nonpolar solvents is, again, an illustration of the chemical axiom "like dissolves like. " Two liquids that do not mix to an appreciable extent are called immiscible. Layers are formed when we pour immiscible liquids into the same container. Gasoline, oil (Figure 11.15), benzene, carbon tetrachloride, some paints, and many other nonpolar liquids are immiscible with water. The attraction between the molecules of such nonpolar liquids and polar water molecules is ineffectively weak. The only strong attractions in such a mixture are between the water molecules, so they effectively squeeze out the molecules of the nonpolar liquid. The distinction between immiscibility and miscibility is really one of degrees, so that miscible liquids are of infinite mutual solubility, while liquids said to be immiscible are of very low (though not zero) mutual solubility. Choices: - silicon bonds - atmospheric bonds - compressed bonds - hydrogen bonds A:
A: hydrogen bonds

Q: Q: Most plates are made up of a combination of what? Read this paragraph and choose the correct option from the provided answers: If you look at the map pictured below, you will see that the lithosphere is divided into plates ( Figure below ). There are a dozen major and several minor plates. Each plate is named for the continent or ocean basin it contains. Some plates are made of all oceanic lithosphere. A few are all continental lithosphere. But most plates are made of a combination of both. Notice the locations where the most earthquake epicenters are found. Choices: - oceanic and reflective lithosphere - continental and battered lithosphere - continental and reflective lithosphere - continental and oceanic lithosphere A:
A: continental and oceanic lithosphere