Given the background: Almost all earthquakes occur at plate boundaries. All types of plate boundaries have earthquakes. Convection within the Earth causes the plates to move. As the plates move, stresses build. When the stresses build too much, the rocks break. The break releases the energy that was stored in the rocks. The sudden release of energy creates an earthquake. During an earthquake the rocks usually move several centimeters or rarely as much as a few meters. Elastic rebound theory describes how earthquakes occur ( Figure below ). and the situation: Two brothers loved geology. Bob studied sedimentary rocks while Dan studied about earthquakes and their location. Answer the following question: Which brother studied more about how rocks usually move a few meters?
Ans: Dan

Given the background: Many chemicals that were once commonly used were later found out to be harmful to the environment , to human health, or both. The element lead was once a common additive to gasoline and to paint. Plumbing pipes were once typically made of lead. Only since the 1970s has the danger of lead become apparent. It causes brain damage and small children (who often chewed on objects painted with lead-based paint) are particularly susceptible. The use of lead in gasoline, paint, and plumbing pipes is now banned and new materials are being developed to replace the hazardous lead components. and the situation: Hank and Brian both grew up in the 1950s. They enjoyed playing with toys, but they each had a personal favorite. Hank's favorite toy as a child was his wooden baseball bat. Brian's favorite toy was a metal model car set that came with paint a child could use to paint the car however they wanted. They both have very fond memories of their childhood and Hank still has the baseball bat and his grandchildren now use it when they visit him. Answer the following question: Which child was less likely exposed to dangerous amounts of lead?
Ans: Hank

Given the background: Cholesterol can't dissolve in the blood. It has to be transported to and from the cells by carriers called lipoproteins. Low-density lipoprotein, or LDL, is known as "bad" cholesterol. High-density lipoprotein (HDL) is known as good cholesterol. When too much LDL cholesterol circulates in the blood, it can slowly build up in the inner walls of the arteries that feed the heart and brain. Together with other substances, it can form plaque, and lead to atherosclerosis. If a clot forms and blocks a narrowed artery, a heart attack or stroke can result. Cholesterol comes from the food you eat as well as being made by the body. To lower bad cholesterol, a diet low in saturated fat and dietary cholesterol should be followed. Regular aerobic exercise also lowers LDL cholesterol and increases HDL cholesterol. and the situation: John is a doctor with the local hospital. Earlier today, he was seeing two patients, patient A and patient B. John found out that patient A had more LDL, but patient B had more HDL. He now needs to determine correct treatment for them. Answer the following question: Would patient A have higher or lower risk of heart attack than patient B?
Ans: higher

Given the background: The epidermis also contains melanocytes , which are cells that produce melanin. Melanin is the brownish pigment that gives skin much of its color. Everyone has about the same number of melanocytes, but the melanocytes of people with darker skin produce more melanin. The amount of melanin produced is determined by heredity and exposure to UV light, which increases melanin output. Exposure to UV light also stimulates the skin to produce vitamin D . Because melanin blocks UV light from penetrating the skin, people with darker skin may be at greater risk of vitamin D deficiency. and the situation: Matt and his brother Jesse are twins. They look almost identical. If it weren't for the fact that Jesse has a slightly darker skin complexion you wouldn't be able to tell them apart. In fact one year Matt was out in the sun for a long time and picked up a bit of a tan so they actually did look exactly alike. Answer the following question: Which persons melanocytes produce more melanin, Matt or Jesse?
Ans: Jesse