Problem: Greg is an electrical engineer. He works for an engineering firm that builds houses. Yesterday, Greg was checking two of the houses. He noticed that one of the houses had short circuit. He labeled that as case A. But the other house didn't have short circuit. He labeled that as case B. Which case would see more current pushing through the wires, case A or case B? Hint: In the wiring of a building, the wires carrying the current in and out are different and never touch directly. The charge passing through the circuit always passes through an appliance (which acts as a resistor) or through another resistor, which limits the amount of current that can flow through a circuit. Appliances are designed to keep current at a relatively low level for safety purposes. The appropriate voltage and resistance in a circuit keeps the current in control and keeps the circuit safe. It is possible, however, for something to happen that causes the wire bringing the current in to come into contact with either the wire carrying the current out or the ground wire, thus causing what is called a short circuit . In a short circuit, some or all of the resistance is cut out of the circuit allowing the voltage to push a huge current through the wires.

A: case A

Problem: Two neighboring islands Grey island and Sand island both contributed to global warming by their actions. Grey island contributed way more because they were more careless. Which island contributed less to extinction? Hint: Another major cause of extinction is global warming , which is also known as global climate change. During the past century, the Earth's average temperature has risen by almost 1C (about 1.3F). You may not think that is significant, but to organisms that live in the wild and are constantly adapting to their environments, any climate change can be hazardous. Recall that burning fossil fuels releases gasses into the atmosphere that warm the Earth. Our increased use of fossil fuels, such as coal and oil, is changing the Earth's climate. Any long-term change in the climate can destroy the habitat of a species. Even a brief change in climate may be too stressful for an organism to survive. For example, if the seas increase in temperature, even briefly, it may be too warm for certain types of fish to reproduce.

A: Sand

Problem: Bob works for a data storage company. He has now three projects, project A, project B, and project C, simultaneously going on. All of them involves storing XML data. Project A has small volume of data, but project B and project C has large volume of data. He applied Fast Infoset format for project B, but didn't apply that format for project C. Which project would have lower access times, project A or project C? Hint: Storing large volumes of data When storing XML to either file or database, the volume of data a system produces can often exceed reasonable limits, with a number of detriments: the access times go up as more data is read, CPU load goes up as XML data takes more power to process, and storage costs go up. By storing XML data in Fast Infoset format, data volume may be reduced by as much as 80 percent.

A: project A

Problem: Two students learned about soils in school. Brad had to study forest soils, while his colleague Frank had to study grasslands. They both did a good job and received A's for their efforts and accumulated knowledge. Which student read more about slow rates of decomposition? Hint: Soil is well developed in the forest as suggested by the thick humus layers, rich diversity of large trees and animals that live there. In forests, precipitation exceeds evapotranspiration which results in an excess of water that percolates downward through the soil layers. Slow rates of decomposition leads to large amounts of fulvic acid, greatly enhancing chemical weathering. The downward percolation, in conjunction with chemical weathering leaches magnesium (Mg), iron (Fe), and aluminum (Al) from the soil and transports them downward, a process known as podzolization. This process leads to marked contrasts in the appearance and chemistry of the soil layers.

A:
Brad