Q: I read this background article the other day: Clouds on Earth are made of water vapor. Venus's clouds are a lot less pleasant. They are made of carbon dioxide, sulfur dioxide and large amounts of corrosive sulfuric acid! The atmosphere of Venus is so thick that the pressure on the surface of Venus is very high. In fact, it is 90 times greater than the pressure at Earth's surface! The thick atmosphere causes a strong greenhouse effect. As a result, Venus is the hottest planet. Even though it is farther from the Sun, Venus is much hotter even than Mercury. Temperatures at the surface reach 465C (860F). That's hot enough to melt lead! I am facing a new situation today: Two friends studied different planets for their school project. Sean studied Earth's atmosphere, while Bill studied Venus's and Mercury's. Using the knowledge I acquired from the background article, how should I answer correctly the following question regarding my new situation: Which friend studied more about clouds made of carbon dioxide?
A: Bill

Q: I read this background article the other day: Old age begins in the mid-60s and lasts until the end of life. Most people over 65 have retired from work, freeing up their time for hobbies, grandchildren, and other interests. Stamina, strength, reflex time, and the senses all decline during old age, and the number of brain cells decreases as well. The immune system becomes less efficient, increasing the risk of serious illnesses such as cancer and pneumonia. Diseases such as Alzheimer's disease that cause loss of mental function also become more common. I am facing a new situation today: Two groups of people participated in a geriatrics study. group D had people over 65 years old, while group Y had people in their 40's in its composition. Using the knowledge I acquired from the background article, how should I answer correctly the following question regarding my new situation: Which group had people at greater risk of developing cancer?
A: group D

Q: I read this background article the other day: Air pollution is harmful to human beings and other living things. About 22 million people die from air pollution each year. Breathing polluted air increases the risk of developing lung diseases such as asthma and lung cancer. Breathing bad air also increases the chances of dying from other diseases. Children are most likely to be affected by air pollution. That's because their lungs are still developing and growing. Children also take in more air for their size than adults do. Some air pollutants damage the environment as well as the health of living things. The type of damage depends on the pollutant. Air pollution can also harm the environment. I am facing a new situation today: Two sister cities had different environments. Shanghai had big problems with air pollution while Berna took very good care of the surrounding environment and air quality. Using the knowledge I acquired from the background article, how should I answer correctly the following question regarding my new situation: Which city had people at decreased risk of developing asthma?
A: Berna

Q: I read this background article the other day: Active transport occurs when a substance passes through the cell membrane with the help of extra energy. This happens when a substance moves from an area where it is less concentrated to an area where it is more concentrated. This is the opposite of diffusion. The substance moves up, instead of down, the concentration gradient. Like rolling a ball uphill, this requires an input of energy. The energy comes from the molecule named ATP (adenosine triphosphate). The energy allows special transport proteins called pumps to move substances to areas of higher concentration. An example is the sodium-potassium pump. I am facing a new situation today: Gary is a high school student examining two cells under a microscope for his biology class. In a petri dish, marked Cell X, Gary sees that substances inside the cell are spreading apart from each other making it less concentrated. In the dish marked Cell Y, Gary sees substances coming together and moving into close proximity to one another. Using the knowledge I acquired from the background article, how should I answer correctly the following question regarding my new situation: Which cell is utilizing diffusion?
A:
Cell X