Q: Why does water infiltrate the ground? Read this paragraph and choose the correct option from the provided answers: Water infiltrates the ground because soil and rock are porous. Between the grains are pores, or tiny holes. Since water can move through this rock it is permeable. Eventually, the water reaches a layer of rock that is not porous and so is impermeable. Water stops moving downward when it reaches this layer of rock. Choices: - gravity - prolonged drought conditions - run-off from flooding - because soil and rocks are porous A:
because soil and rocks are porous
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Q: What is an interesting example of a molecule with two central atoms, which are both c atoms? Read this paragraph and choose the correct option from the provided answers: Acetylene is an interesting example of a molecule with two central atoms, which are both C atoms. Polyatomic ions are bonded together with covalent bonds. Because they are ions, however, they participate in ionic bonding with other ions. So both major types of bonding can occur at the same time. Choices: - chloride - water - sulfur - acetylene A:
acetylene
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Q: Land plants are classified into two major groups according to the absence or presence of what tissue? Read this paragraph and choose the correct option from the provided answers: The Major Divisions of Land Plants Land plants are classified into two major groups according to the absence or presence of vascular tissue, as detailed in Figure 14.8. Plants that lack vascular tissue formed of specialized cells for the transport of water and nutrients are referred to as nonvascular plants. The bryophytes, liverworts, mosses, and hornworts are seedless and nonvascular, and likely appeared early in land plant evolution. Vascular plants developed a network of cells that conduct water and solutes through the plant body. The first vascular plants appeared in the late Ordovician (461444 million years ago) and were probably similar to lycophytes, which include club mosses (not to be confused with the mosses) and the pterophytes (ferns, horsetails, and whisk ferns). Lycophytes and pterophytes are referred to as seedless vascular plants. They do not produce seeds, which are embryos with their stored food reserves protected by a hard casing. The seed plants form the largest group of all existing plants and, hence, dominate the landscape. Seed plants include gymnosperms, most notably conifers, which produce "naked. Choices: - disease - root - bacterial - vascular A:
vascular
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Q: What causes rivers to always flow downhill? Read this paragraph and choose the correct option from the provided answers: Currents are like rivers flowing through the ocean. Rivers always flow downhill because of gravity. What do you think causes ocean currents to flow?. Choices: - slope - pressure - diffusion - gravity A:
gravity
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