Question: Q: What source of water pollution picks up chemicals from the ground with water and carries them to bodies of water? Read this paragraph and choose the correct option from the provided answers: Water pollution comes from many sources. One of the biggest sources is runoff. Runoff picks up chemicals such as fertilizer from agricultural fields, lawns, and golf courses. It carries the chemicals to bodies of water. The added nutrients from fertilizer often cause excessive growth of algae, creating algal blooms (see Figure below ). The algae use up oxygen in the water so that other aquatic organisms cannot survive. This has occurred over large areas of the ocean, creating dead zones , where low oxygen levels have killed all ocean life. A very large dead zone exists in the Gulf of Mexico. Measures that can help prevent these problems include cutting down on fertilizer use. Preserving wetlands also helps because wetlands filter runoff. Choices: - fertilizer - erosion - sediment - runoff A:
Answer: runoff

Question: Q: What is the method of setting or correcting a measuring device by matching it to known measurement standards called? Read this paragraph and choose the correct option from the provided answers: When using measuring devices, we often use a technique called calibration to increase the accuracy of our measurements. Calibration is a method of setting or correcting a measuring device by matching it to known measurement standards. To better understand calibration, we will look at the example of calibrating a thermometer. All thermometers are slightly different in their temperature readings. One way to calibrate a thermometer is by using the freezing point and boiling point of water ( Figure below ). If we know that water freezes at 0C and boils at 100C, we can calibrate our thermometer by measuring the temperature of ice water and of boiling water. We place the thermometer in ice water and wait for the thermometer liquid to reach a stable height, then place a mark at this height which represents 0C. Then we place the thermometer in boiling water, and after waiting for the thermometer liquid to reach a stable height, we place a mark at this height which represents 100C. We can then place 100 equally spaced divisions between our 0 and 100C marks to each represent 1C. Our thermometer has now been calibrated using the known values for the freezing point and boiling point of water, and can be used to measure temperatures of objects between 0 and 100C. Choices: - parallax - distortion - precision - calibration A:
Answer: calibration

Question: Q: Which class of acids acetic acid (ch 3 cooh) belongs to? Read this paragraph and choose the correct option from the provided answers: Not all hydrogen atoms in molecular compounds are ionizable. In methane (CH 4 ), the hydrogen atoms are covalently bonded to carbon in bonds that are only slightly polar. The hydrogen atoms are not capable of ionizing and methane has no acidic properties. Acetic acid (CH 3 COOH) belongs to a class of acids called organic acids. There are four hydrogen atoms in the molecule, but only the one hydrogen that is bonded to an oxygen atom is ionizable. Choices: - anorganic acids - strong acids - common acids - organic acids A:
Answer:
organic acids