Tag: science & technology

Einstein received the Nobel Prize in Physics (1921), was named Time Person of the Century (1999), received the Max Planck Medal (1929), and the Copley Medal (1925). The Lorentz Medal, awarded by the Dutch Royal Academy, was not among his many honors.

Importing food requires significant energy for transportation (shipping, air freight), refrigeration during transit, and storage. For many perishable foods imported over long distances, the fossil fuel energy expended can exceed the caloric energy content of the food itself.

One gallon of motor oil can indeed contaminate approximately one million gallons of freshwater, creating an oil slick that spreads over acres. This is why proper oil disposal is critical for environmental protection. The EPA and environmental agencies widely cite this statistic.

Coal combustion is the largest single source of anthropogenic carbon dioxide emissions globally, contributing more than oil or natural gas. Burning coal releases more CO2 per unit of energy than other fossil fuels. This makes it the primary driver of human-made atmospheric CO2 increase.

The statement is TRUE. "Clean coal" technology (carbon capture and storage) requires additional energy to operate, meaning more coal must be burned to generate the same amount of electricity. Estimates suggest 15-25% more coal is needed. This creates a paradox - you need more mining (which itself is carbon-intensive) to achieve lower emissions at the plant.

The statement is TRUE. Approximately 71% of Earth's surface is covered by water (often rounded to 75% in general discussions). Of that water, about 97.5% is saltwater in oceans. Only about 2.5-3% is freshwater, and most of that freshwater is locked in glaciers and ice caps, leaving less than 1% as accessible liquid freshwater.

In this Java for loop, i starts at 0 and increments while i < 11. The loop runs for i values 0, 1, 2, ..., 10. When i becomes 11, the condition i < 11 is false, so the loop terminates. At termination, i equals 11.

To access superclass members from a subclass, the members must be declared with appropriate access (protected or public) and then accessed using the 'super' keyword. Option A is incomplete because it doesn't specify the access modifier requirement. Option B is wrong because private members are not accessible outside the class. Option D is incorrect because superclass members can indeed be accessed if properly declared.

In Java, primitive data types are the basic built-in types that are not objects. 'int' and 'float' are both primitive types - int is a 32-bit integer and float is a 32-bit floating-point number. Array (B) is not a primitive type - it's a reference type/object. String (C) is also not primitive - it's a class from the java.lang package.