I read this background article the other day: Hepatitis B is a disease of the liver. It is caused by a virus called hepatitis B, which can be passed through sexual activity. Hepatitis B causes vomiting. It also causes yellowing of the skin and eyes. The disease goes away on its own in some people. Other people are sick for the rest of their lives. In these people, the virus usually damages the liver. It may also lead to liver cancer. Medicines can help prevent liver damage in these people. There is also a vaccine to protect against hepatitis B.  I am facing a new situation today: Mike and John are brothers. Their dad sent them to the doctor's office to get tested for hepatitis because Mike was feeling sick all the time. It turned out Mike has hepatitis B, while John doesn't.  Using the knowledge I acquired from the background article, how should I answer correctly the following question regarding my new situation: Which brother doesn't have a disease which causes yellowing of the skin?
Ans: John

I read this background article the other day: A thermometer is a device used to measure temperature. It is placed in contact with an object and allowed to reach thermal equilibrium with the object (they will have the same temperature). The operation of a thermometer is based on some property, such as volume, that varies with temperature. The most common thermometers contain liquid mercury, or some other liquid, inside a sealed glass tube. The liquid expands and contracts faster than the glass tube. Therefore, when the temperature of the thermometer increases, the liquid volume expands faster than the glass volume, allowing the liquid to rise in the tube. The positions of the liquid in the tube can then be calibrated for accurate temperature readings. Other properties that change with temperature can also be used to make thermometers; liquid crystal colors and electrical conductivity change with temperature, and are also relatively common thermometers.  I am facing a new situation today: A group of middle school students is measuring the temperature of various liquids for a chemistry lab using a mercury thermometer. They have a beaker of boiling water, a beaker of ice water, and a beaker of water at room temperature.  Using the knowledge I acquired from the background article, how should I answer correctly the following question regarding my new situation: If the students move the thermometer from the room temperature water into the boiling water water will the mercury level go up or down?
Ans: up

I read this background article the other day: Animals and some bacteria and fungi carry out lactic acid fermentation. Lactic acid is a waste product of this process. Our muscles perform lactic acid fermentation during strenuous exercise, since oxygen cannot be delivered to the muscles quickly enough. The buildup of lactic acid is believed to make your muscles sore after exercise. Bacteria that produce lactic acid are used to make cheese and yogurt. The lactic acid causes the proteins in milk to thicken. Lactic acid also causes tooth decay, because bacteria use the sugars in your mouth for energy.  I am facing a new situation today: A group of students in biology class studied fermentation. Team A studied alcoholic fermentation, while team B learned more about lactic fermentation. They later organised a trivia contest between teams.  Using the knowledge I acquired from the background article, how should I answer correctly the following question regarding my new situation: Which team studied more about cheese and yogurt?
Ans: team B

I read this background article the other day: Anemophilous pollen grains are light and non-sticky, so that they can be transported by air currents. They are typically 20–60 micrometres (0.0008–0.0024 in) in diameter, although the pollen grains of Pinus species can be much larger and much less dense. Anemophilous plants possess well-exposed stamens so that the pollens are exposed to wind currents and also have large and feathery stigma to easily trap airborne pollen grains. Pollen from anemophilous plants tends to be smaller and lighter than pollen from entomophilous ones, with very low nutritional value to insects. However, insects sometimes gather pollen from staminate anemophilous flowers at times when higher-protein pollens from entomophilous flowers are scarce. Anemophilous pollens may also be inadvertently captured by bees' electrostatic field. This may explain why, though bees are not observed to visit ragweed flowers, its pollen is often found in honey made during the ragweed floral bloom. Other flowers that are generally anemophilous are observed to be actively worked by bees, with solitary bees often visiting grass flowers, and the larger honeybees and bumblebees frequently gathering pollen from corn tassels and other grains.  I am facing a new situation today: Frank owned two parcels of land. He called them Forest and Field. The Forest parcel was covered in old-growth pine, while Field one was covered in grass and wildflowers. Frank was very proud of his properties.  Using the knowledge I acquired from the background article, how should I answer correctly the following question regarding my new situation: Which parcel had fewer plants with anemophilous pollen grains?
