Joel has just started his first day working as a scientist in a laboratory. The first task he was given is to look at two atoms and to jot down as much information about the two as he can. First, he needs to come up with an identification for these atoms. Since he is new, he decides to keep it professional and simply call the larger of the two atoms "atom L" and the smaller one "atom S". Now that he's taken care of that he can get down to work. Is the shielding effect in atom L higher or lower than in atom S? Hint: The ionization energies of the representative elements generally decrease from top to bottom within a group. This trend is explained by the increase in size of the atoms within a group. The valence electron that is being removed is further from the nucleus in the case of a larger atom. The attractive force between the valence electron and the nucleus weakens as the distance between them increases and as the shielding effect increases, resulting in a lower ionization energy for the larger atoms within a group. Although the nuclear charge is increased for larger atoms, the shielding effect also increases due to the presence of a larger number of inner electrons. This is particularly easy to see in the alkali metals, where the single valence electron is shielded by all of the inner core electrons.
Ans: higher

Barry and Will are two geologists. Barry is specialized in subduction zones and new seafloor. Will is specialized in montology. Which person learned more about the Mid-Atlantic Ridge? Hint: As new seafloor forms and spreads apart from the mid-ocean ridge it slowly cools over time. Older seafloor is, therefore, colder than new seafloor, and older oceanic basins deeper than new oceanic basins due to isostasy. If the diameter of the earth remains relatively constant despite the production of new crust, a mechanism must exist by which crust is also destroyed. The destruction of oceanic crust occurs at subduction zones where oceanic crust is forced under either continental crust or oceanic crust. Today, the Atlantic basin is actively spreading at the Mid-Atlantic Ridge. Only a small portion of the oceanic crust produced in the Atlantic is subducted. However, the plates making up the Pacific Ocean are experiencing subduction along many of their boundaries which causes the volcanic activity in what has been termed the Ring of Fire of the Pacific Ocean. The Pacific is also home to one of the world's most active spreading centers (the East Pacific Rise) with spreading rates of up to 13 cm/yr. The Mid-Atlantic Ridge is a "textbook" slow-spreading center, while the East Pacific Rise is used as an example of fast spreading. Spreading centers at slow and intermediate rates exhibit a rift valley while at fast rates an axial high is found within the crustal accretion zone. The differences in spreading rates affect not only the geometries of the ridges but also the geochemistry of the basalts that are produced.Since the new oceanic basins are shallower than the old oceanic basins, the total capacity of the world's ocean basins decreases during times of active sea floor spreading. During the opening of the Atlantic Ocean, sea level was so high that a Western Interior Seaway formed across North America from the Gulf of Mexico to the Arctic Ocean.
Ans: Barry

Rob is experimenting with how air pressure works. To that end, he has designed two tests. In the first test the air flow works as it would in an airplane wing. He labels it as case A. In the second test the air flow works as it would in a race car spoiler. He labels it as case B. He is surprised to see that air flow behaves differently in different situations. In which case the air pressure above would be higher, case A or case B? Hint: Bernoulli's law explains how the wings of both airplanes and birds create lift that allows flight (see Figure below ). The shape of the wings causes air to flow more quickly and air pressure to be lower above the wings than below them. This allows the wings to lift the plane or bird above the ground against the pull of gravity. A spoiler on a race car, like the one in Figure below , works in the opposite way. Its shape causes air to flow more slowly and air pressure to be greater above the spoiler than below it. As a result, air pressure pushes the car downward, giving its wheels better traction on the track.
Ans: case B

Two islands of identical size with similar ecosystems experienced different destinies. Caribu island, inhabited by more natives, hunted a few of the animal species there, contributing to the extinction of a few. People from Hiji island, were pescotarian, and hardly ever fished. Which island exterminated less species of animals? Hint: Biodiversity loss is the extinction of species (plant or animal) worldwide, and also the local reduction or loss of species in a certain habitat. The latter phenomenon can be temporary or permanent, depending on whether the environmental degradation that leads to the loss is reversible through ecological restoration / ecological resilience or effectively permanent (e.g. through land loss). Global extinction has so far been proven to be irreversible. Even though permanent global species loss is a more dramatic phenomenon than regional changes in species composition, even minor changes from a healthy stable state can have dramatic influence on the food web and the food chain insofar as reductions in only one species can adversely affect the entire chain (coextinction), leading to an overall reduction in biodiversity, possible alternative stable states of an ecosystem notwithstanding. Ecological effects of biodiversity are usually counteracted by its loss. Reduced biodiversity in particular leads to reduced ecosystem services and eventually poses an immediate danger for food security, also for humankind.[1]
Ans: Hiji