Q: Given the background: Depleted soils can be protected from soil erosion by groundcover plants such as naturally growing grasses in agroforestry systems. These help to stabilise the soil as they increase cover compared to short-cycle cropping systems. Soil cover is a crucial factor in preventing erosion. Cleaner water through reduced nutrient and soil surface runoff can be a further advantage of agroforestry. The runoff can be reduced by decreasing its velocity and increasing infiltration into the soil. Compared to row-cropped fields nutrient uptake can be higher and reduce nutrient loss into streams.Further advantages concerning plant growth: and the situation: Rob is an environmental scientist. He was doing a study on agroforestry. To test the sustainability of agroforestry he conducted two pilot projects, pilot A and pilot B. In pilot A, he used a land for agrofroestry. In pilot B, he used a land for usual row-cropping. He needed to find the pros and cons of both systems. Answer the following question: Would pilot A see less or more clean water than pilot B?
A: more

Q: Given the 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. and the situation: Beijing recently opened several new coal-fired power plants over the last few months. In Montreal, there have been large reductions in sulfur oxides produced by manufacturing plants after a recent referendum. Answer the following question: Which area is less likely to have acid rain?
A: Montreal

Q: Given the 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. and the situation: Blue island and Red island were two big sister islands situated 100 miles from each other. People on Blue island used gas powered vehicles, while people on Red island used electrical vehicles. The people on Blue island presented more respiratory problems. Answer the following question: Which island had more days with smog?
A: Blue

Q: Given the background: Another example of incomplete dominance is with sickle cell anemia, a disease in which a blood protein called hemoglobin is produced incorrectly. This causes the red blood cells to have a sickle shape, making it difficult for these misshapen cells to pass through the smallest blood vessels. A person that is homozygous recessive ( ss ) for the sickle cell trait will have red blood cells that all have the incorrect hemoglobin. A person who is homozygous dominant ( SS ) will have normal red blood cells. and the situation: Two sisters named Mary and Ann went in for a blood test and found out that Mary had sickle cell anemia. Ann was normal. Answer the following question: Which sister did not have a disease in which a blood protein called hemoglobin is produced incorrectly?
A:
Ann