*Question*
Answer the following question given this paragraph: The Water (Hydrologic) Cycle Water is the basis of all living processes. The human body is more than 1/2 water and human cells are more than 70 percent water. Thus, most land animals need a supply of fresh water to survive. However, when examining the stores of water on Earth, 97.5 percent of it is non-potable salt water (Figure 46.12). Of the remaining water, 99 percent is locked underground as water or as ice. Thus, less than 1 percent of fresh water is easily accessible from lakes and rivers. Many living things, such as plants, animals, and fungi, are dependent on the small amount of fresh surface water supply, a lack of which can have massive effects on ecosystem dynamics. Humans, of course, have developed technologies to increase water availability, such as digging wells to harvest groundwater, storing rainwater, and using desalination to obtain drinkable water from the ocean. Although this pursuit of drinkable water has been ongoing throughout human history, the supply of fresh water is still a major issue in modern times. Q: The primary substance that human cells, and ultimately human beings, are made up of is what? Choices: - air - oil - gas - water A:
**Answer**
water

*Question*
Answer the following question given this paragraph: Chlorine is the active ingredient in household bleach. It removes stains from clothes. It can also be used to disinfect countertops and other surfaces. Q: What is the active ingredient in household bleach? Choices: - magnesium - oxygen - iodine - chlorine A:
**Answer**
chlorine

*Question*
Answer the following question given this paragraph: Sulfur Oxygen Compounds The two common oxides of sulfur are sulfur dioxide, SO2, and sulfur trioxide, SO3. The odor of burning sulfur comes from sulfur dioxide. Sulfur dioxide, shown in Figure 18.47, occurs in volcanic gases and in the atmosphere near industrial plants that burn fuel containing sulfur compounds. Q: What sulfur compound occurs in volcanic gases and in the atmosphere near industrial plants? Choices: - sulfur hydroxide - carbon sulfide - nitrogen sulfide - sulfur dioxide A:
**Answer**
sulfur dioxide

*Question*
Answer the following question given this paragraph: Albedo is the amount of light reflected by a surface. Sea ice has an albedo of .85, meaning 85% of light is reflected back from its surface (and leaves the Earth) and 15% is absorbed and stays in the Earth; ice-free water has an albedo of .07. (93% of the solar energy is absorbed. ) Thus the observed melting of sea ice could amplify the effect of global warming. Q: What is the scientific term for the amount of light reflected by a surface? Choices: - prism - inversion - reactivity - albedo A:
**Answer**
albedo