You are given a new situation: Two lakes had been stocked with fish two years before.Blue lake had an abundant fish stock because nobody fished there, but Green lake was open for fishing. Blue lake had some pollution, cannibalism and disease problems. and a hint : Fish mortality is a parameter used in fisheries population dynamics to account for the loss of fish in a fish stock through death. The mortality can be divided into two types: Natural mortality: the removal of fish from the stock due to causes not associated with fishing. Such causes can include disease, competition, cannibalism, old age, predation, pollution or any other natural factor that causes the death of fish. In fisheries models natural mortality is denoted by (M).[1] Fishing mortality: the removal of fish from the stock due to fishing activities using any fishing gear.[1] It is denoted by (F) in fisheries models. Please answer this question : Which lake had more fish disease problems?
Ans: Blue lake

You are given a new situation: Lucy and Sarah are two people who each own a lake that they enjoy spending time at. They have to take care of the lake though and make sure everything is healthy so that the lake can continue to thrive and people will want to visit it. Sarah says she heard a secret that if you dump fertilizer into your lake, the fish will grow twice as large. Sarah says she has just started doing it this past week and can't wait to see the results. Lucy is skeptical and waits to see what happens at Sarah's lake. and a hint : 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. Please answer this question : Will Lucy or Sarah have a lake with more plants in it?
Ans: Sarah

You are given a new situation: Two geology students had an exam on plate tectonics. Bobby learned more about divergent tectonic plates, while Nate was more confident in explaining everything about Convergent plates. and a hint : Seafloor spreading helps explain continental drift in the theory of plate tectonics. When oceanic plates diverge, tensional stress causes fractures to occur in the lithosphere. The motivating force for seafloor spreading ridges is tectonic plate pull rather than magma pressure, although there is typically significant magma activity at spreading ridges. At a spreading center, basaltic magma rises up the fractures and cools on the ocean floor to form new seabed. Hydrothermal vents are common at spreading centers. Older rocks will be found farther away from the spreading zone while younger rocks will be found nearer to the spreading zone. Additionally spreading rates determine if the ridge is fast, intermediate, or slow. As a general rule, fast ridges have spreading (opening) rates of more than 9 cm/year. Intermediate ridges have a spreading rate of 59 cm/year while slow spreading ridges have a rate less than 5 cm/year. Please answer this question : Which student knew less about Hydrothermal vents?
Ans: Nate

You are given a new situation: Pam and Angela live in different cities and are talking to each other on the phone while they are sitting outside. Pam lives in Dunder, a city located at sea level, and Angela lives in Mifflin, a city up high in the mountains. Although they don't get to see each other much any more due to the distance between them, they make sure to stay in regular contact. and a hint : As shown here, pressure decreases to less than 25% of ground-level atmospheric pressure when we get to an altitude of about six miles. Since this is a common cruising altitude for commercial airplanes, pressurized cabins are needed for the comfort and survival of the passengers. This is because the density of the air decreases along with the decreasing air pressure, so there is less oxygen in a breath of air. You've probably noticed this effect in high-mountain areas, as it often feels harder to breath. Please answer this question : Which woman gets more oxygen per single breath?
Ans: Pam