Q: I have a new situation: Two college students both had unprotected sex with different partners. Ben got the HIV virus, while Nate was lucky and was not infected with any diseases. But I can use this background: HIV , or human immunodeficiency virus, causes AIDS. AIDS stands for "acquired immune deficiency syndrome." It is a condition that causes death and does not have a known cure. AIDS usually develops 10 to 15 years after a person is first infected with HIV. The development of AIDS can be delayed with proper medicines. The delay can be well over 20 years with the right medicines. Today, individuals who acquire HIV after 50 years of age can expect to reach an average human life span. What is an answer for this question: Which student had a lower chance of dying earlier than normal?
A: Nate

Q: I have a new situation: John studies how chemicals affect environment. He traveled to the Amish country to see their traditional ways of farming. He noticed they don't use any fertilizers or pesticides. He labeled this part of the study as case A. Then he visited a modern farming facility where they use tons of fertilizers and pesticides. He labeled this part of the study as case B. But I can use this background: Huge amounts of chemicals, such as fertilizers and pesticides, are applied to farm fields (see Figure below ). Some of the chemicals are picked up by rainwater. Runoff then carries the chemicals to nearby rivers or lakes. Dissolved fertilizer causes too much growth of water plants and algae. This can lead to dead zones where nothing can live in lakes and at the mouths of rivers. Some of the chemicals can infiltrate into groundwater. The contaminated water comes up in water wells. If people drink the polluted water, they may get sick. What is an answer for this question: Which place would see more growth of algae, case A or case B?
A: case B

Q: I have a new situation: Two friends were into natural sciences. Tom was more into Geology, while Rick studied Ecology. But I can use this background: Ecology is the study of ecosystems. An ecosystem consists of all the living and nonliving components of the habitat. Whereas nutrients and certain elements are recycled through ecosystems, energy moves in just one direction. Many interactions among species within an ecosystem are centered around the flow of energy. The formation of ecosystems, from new land to current habitats, is usually based on the pioneer species, and these species are able to live in an area due to the nonliving factors, such as the climate, the soil and the amount of rainfall, of that area. The populations within an ecosystem also determine the stability of the system. Recent tremendous increases in the human population have raised many important ecological issues. What is an answer for this question: Which student read less about the many interactions among species within an ecosystem?
A: Tom

Q: I have a new situation: Two nearby villages are experiencing earthquakes. Bow village gets a lot of earthquakes annually, while Arrow village gets only a few. But I can use this 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 is an earthquake. During an earthquake the rocks usually move several centimeters. Rarely, they may move as much as a few meters. Elastic rebound theory describes how earthquakes occur ( Figure below ). What is an answer for this question: Which village experiences fewer plates moving?
A:
Arrow