Problem: I can use this background: One result of air pollution is acid rain. Acid rain is precipitation with a low (acidic) pH. This rain can be very destructive to wildlife. When acid rain falls in forests, freshwater habitats, or soils, it can kill insects and aquatic life. It causes this damage because of its very low pH. Sulfur oxides and nitrogen oxides in the air both cause acid rain to form ( Figure below ). Sulfur oxides are chemicals that are released from coal-fired power plants. Nitrogen oxides are released from motor vehicle exhaust. Now, I have a new situation: Two counties paid a study about acid rain. They found out Hill county had experienced that, while New county hadn't. Answer this question please: Which county experienced less precipitation destructive to wildlife?

A: New

Problem: I can use this background: Gasoline-powered vehicles emit a lot of harmful materials. Nitrogen oxides are formed when atmospheric nitrogen reacts with oxygen at the high temperatures found in a car engine. Carbon monoxide is a by-product of incomplete combustion of hydrocarbons. Evaporated and unused fuel releases volatile hydrocarbons into the atmosphere to help form smog. The presence of a catalytic converter in the exhaust system of the car causes these materials to react and be changed into less harmful products. Now, I have a new situation: Hill town was full of gasoline powered vehicles, while Valley town 50 miles away, banned all gas powered vehicles and allows only electrical vehicles or horse-and-buggies. Answer this question please: Which town had more volatile hydrocarbons in the atmosphere?

A: Hill

Problem: I can use this background: A period of very low rainfall occurred while the Grants were on the islands. The drought resulted in fewer seeds for the finches to eat. Birds with smaller beaks could eat only the smaller seeds. Birds with bigger beaks were better off. They could eat seeds of all sizes. Therefore, there was more food available to them. Many of the small-beaked birds died in the drought. More of the big-beaked birds survived and reproduced. Within just a couple of years, the average beak size in the finches increased. This was clearly evolution by natural selection. Now, I have a new situation: Two bird islands in the Atlantic Ocean had very different climate changes during the last 5 years. Bone island experienced drought, while Finch island experienced flooding. Answer this question please: Which island had none of the big-beaked birds die?

A: Finch

Problem: I can use this background: In practice, the diameter of the aperture is chosen based on the focal length of the lens, the diameter and quality of the input beam, and its wavelength (longer wavelengths require larger apertures). If the hole is too small, the beam quality is greatly improved but the power is greatly reduced. If the hole is too large, the beam quality may not be improved as much as desired. The size of aperture that can be used also depends on the size and quality of the optics. To use a very small pinhole, one must use a focusing lens with a low f-number, and ideally the lens should not add significant aberrations to the beam. The design of such a lens becomes increasingly more difficult as the f-number decreases. Now, I have a new situation: David needs to purchase a camera for his photography class. He went to the local consumer electronics store to find himself a good camera. Two cameras caught his eye, camera A and camera B. Camera A had a very small pinhole, but camera B had larger aperture. David needs to decide which camera should he buy. Answer this question please: Would camera A have higher or lower beam quality?

A:
higher