Problem: The quantity of small plastic fragments floating in the north-east Pacific Ocean increased a hundredfold between 1972 and 2012.Marine pollution is a generic term for the harmful entry into the ocean of chemicals or particles. The main culprits are those using the rivers for disposing of their waste. The rivers then empty into the ocean, often also bringing chemicals used as fertilizers in agriculture. The excess of oxygen-depleting chemicals in the water leads to hypoxia and the creation of a dead zone.Marine debris, also known as marine litter, is human-created waste that has ended up floating in a lake, sea, ocean, or waterway. Oceanic debris tends to accumulate at the center of gyres and coastlines, frequently washing aground where it is known as beach litter.In addition, the Pacific Ocean has served as the crash site of satellites, including Mars 96, Fobos-Grunt, and Upper Atmosphere Research Satellite. Robert and his brother Jeff are both farmers whose farms are near large rivers. These rivers eventually flow into the Pacific Ocean. Robert recently switched to a different brand of fertilizer to increase the yield on his crops. This fertilizer contains a chemical that tends to destroy oxygen when it comes into contact with it. Due to heavy rains on his farm, large amounts of this fertilizer have been leaking into the river near Robert's farm. Meanwhile, Jeff uses fertilizer that is very stable and does not leak into the rivers near his farm. Who will contribute less to the formation of dead zones in the Pacific Ocean?

A: Jeff

Problem: Soil piping is a particular form of soil erosion that occurs below the soil surface. It causes levee and dam failure, as well as sink hole formation. Turbulent flow removes soil starting at the mouth of the seep flow and the subsoil erosion advances up-gradient. The term sand boil is used to describe the appearance of the discharging end of an active soil pipe.Soil salination is the accumulation of free salts to such an extent that it leads to degradation of the agricultural value of soils and vegetation. Consequences include corrosion damage, reduced plant growth, erosion due to loss of plant cover and soil structure, and water quality problems due to sedimentation. Salination occurs due to a combination of natural and human-caused processes. Arid conditions favour salt accumulation. This is especially apparent when soil parent material is saline. Irrigation of arid lands is especially problematic. All irrigation water has some level of salinity. Irrigation, especially when it involves leakage from canals and overirrigation in the field, often raises the underlying water table. Rapid salination occurs when the land surface is within the capillary fringe of saline groundwater. Soil salinity control involves watertable control and flushing with higher levels of applied water in combination with tile drainage or another form of subsurface drainage. The city of Reslie is known for its grilled cheese sandwiches. People come from all over the world to taste their sandwiches. The mayor of Reslie, while having a meeting about how to spend the excess funds from tourism this year, was told that the city is experiencing soil piping. The neighboring city, Tichago, consumes many of Reslie's grilled cheese sandwiches. The mayor of Tichago has just received a phone call from the mayor of Reslie asking if Tichago is also having soil piping. Tichago's mayor replies that no, they are not. Which city will need to inspect their dams less often?

A: Tichago

Problem: As new changes in the DNA sequence are constantly being generated in a population's gene pool (changing the population's allele frequencies), some of these changes will be beneficial and result in traits that allow adaptation and survival. Natural selection causes evolution of a species as these beneficial traits become more common within a population. Evolution can occur within a species without completely resulting in a new species. Therefore, evolution and speciation are not the same. Over time a species of bird has changed a lot. Originally the climate the bird lived in changed so they adapted and more of them were seen to have heavy down feathers for warmth. Later down the line it got warmer, some of the birds stayed in the warmer area and adapted to it growing thinner feathers. Some of the others decided to migrate to colder areas instead. More time passed and the birds in the warmer area eventually evolved into a very dangerous creature with sharp talons to defend itself from predators. The birds that moved to the colder environment had less predators so they remained basically harmless.. Which birds is likely a case of speciation, the birds living in the cold area or the warm area?

A: warm area

Problem: For an inclined plane, the input distance is the length of the sloping surface, and the output distance is the maximum height of the inclined plane. This was illustrated in Figure above . Because the sloping surface is always greater than the height of the inclined plane, the ideal mechanical advantage of an inclined plane is always greater than 1. An inclined plane with a longer sloping surface relative to its height has a gentler slope. An inclined plane with a gentler slope has a greater mechanical advantage and requires less input force to move an object to a higher elevation. John works as a mechanical engineer in the auto industry. He is testing three surfaces, surface A, surface B, and surface C for their usability. Surface A has a gentler slope, surface B has a steeper slope, and surface C doesn't have any sloping. He needs to figure out advantages and disadvantages of each slope. Would surface A need less or more input force to move an object upward?

A:
less