I have a new situation: The ecologist moved from Aspen, where there was no air pollution, to Seattle which experienced a lot of air pollution. He started studying the weather there as well. But 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. What is an answer for this question: Which city had rain with a higher pH?
Ans: Aspen

I have a new situation: Catherine is throwing her friend a birthday party and is starting to put up decorations. She has finished hanging streamers and now she has to fill the balloons. Having never used a helium tank before, she wants to test how much to fill each balloon. But I can use this background: All fluids exert pressure like the air inside a tire. The particles of fluids are constantly moving in all directions at random. As the particles move, they keep bumping into each other and into anything else in their path. These collisions cause pressure, and the pressure is exerted equally in all directions. When particles are crowded together in one part of an enclosed space, such as the air particles first entering a tire, they quickly spread out to fill all the available space. That's because particles of fluids always move from an area of higher pressure to an area of lower pressure. This explains why air entering a tire through a tiny opening quickly fills the entire tire. What is an answer for this question: If it only took two seconds to fill a balloon at first, but now it takes three seconds has the tank pressure increased or decreased?
Ans: decreased

I have a new situation: Two groups f people presented allergy symptoms. Group Alpha inhaled some allergens, but they were in a very protected environment, while Group Beta ingested some allergens and was exposed to a wide variety of other allergens. But I can use this background: An allergy is a disease in which the immune system makes an inflammatory response to a harmless antigen . Any antigen that causes an allergy is called an allergen. Allergens may be inhaled or ingested, or they may come into contact with the skin. Two common causes of allergies are shown in Figure below . Inhaling ragweed pollen may cause coughing and sneezing. Skin contact with oils in poison ivy may cause an itchy rash. Other common causes of allergies include dust mites, mold, animal dander, insect stings, latex, and certain food and medications. Symptoms of a common allergy such as pollen can include sneezing, a runny nose, nasal congestion and itchy, watery eyes. What is an answer for this question: Which group had some people that were exposed to pollen?
Ans: Group Beta

I have a new situation: Two botanists studied different types of plants. Barb studied anemophilous plants, while her friend Faye learned about entomophilous plants. But I can use this background: Anemophilous pollen grains are light and non-sticky, so that they can be transported by air currents. They are typically 2060 micrometres (0.00080.0024 in) in diameter, although the pollen grains of Pinus species can be much larger and much less dense. Anemophilous plants possess well-exposed stamens so that the pollens are exposed to wind currents and also have large and feathery stigma to easily trap airborne pollen grains. Pollen from anemophilous plants tends to be smaller and lighter than pollen from entomophilous ones, with very low nutritional value to insects. However, insects sometimes gather pollen from staminate anemophilous flowers at times when higher-protein pollens from entomophilous flowers are scarce. Anemophilous pollens may also be inadvertently captured by bees' electrostatic field. This may explain why, though bees are not observed to visit ragweed flowers, its pollen is often found in honey made during the ragweed floral bloom. Other flowers that are generally anemophilous are observed to be actively worked by bees, with solitary bees often visiting grass flowers, and the larger honeybees and bumblebees frequently gathering pollen from corn tassels and other grains. What is an answer for this question: Which botanist learned less about well-exposed stamens?
Ans: Faye