Problem: Please answer a question about the following article about Wood:
There is a strong relationship between the properties of wood and the properties of the particular tree that yielded it. The density of wood varies with species. The density of a wood correlates with its strength (mechanical properties). For example, mahogany is a medium-dense hardwood that is excellent for fine furniture crafting, whereas balsa is light, making it useful for model building. One of the densest woods is black ironwood.
Is mahogany a hardwood or a softwood?
A: hardwood
Problem: Please answer a question about the following article about Friedrich Hayek:
For Hayek, the supposedly stark difference between authoritarianism and totalitarianism has much importance and Hayek places heavy weight on this distinction in his defence of transitional dictatorship. For example, when Hayek visited Venezuela in May 1981, he was asked to comment on the prevalence of totalitarian regimes in Latin America. In reply, Hayek warned against confusing "totalitarianism with authoritarianism," and said that he was unaware of "any totalitarian governments in Latin America. The only one was Chile under Allende". For Hayek, however, the word 'totalitarian' signifies something very specific: the want to "organize the whole of society" to attain a "definite social goal" which is stark in contrast to "liberalism and individualism".
Hayek believed that authoritarianism was very different from what?
A: totalitarianism
Problem: Please answer a question about the following article about Carnival:
Some of the best-known traditions, including carnal parades and masquerade balls, were first recorded in medieval Italy. The carnival of Venice was, for a long time, the most famous carnival (although Napoleon abolished it in 1797 and only in 1979 was the tradition restored). From Italy, Carnival traditions spread to Spain, Portugal and France and from France to New France in North America. From Spain and Portugal it spread with colonization to the Caribbean and Latin America. In the early 19th century in the German Rhineland and Southern Netherlands, the weakened medieval tradition also revive. Continuously in the 18th and 19th centuries CE, as part of the annual Saturnalia abuse of the carnival in Rome, rabbis of the ghetto were forced to march through the city streets wearing foolish guise, jeered upon and pelted by a variety of missiles from the crowd. A petition of the Jewish community of Rome sent in 1836 to Pope Gregory XVI to stop the annual anti-semitic Saturnalia abuse got a negation: "It is not opportune to make any innovation."
What city's carnival was the most famous for a long time?
A: Venice
Problem: Please answer a question about the following article about Electric motor:
Stepper motors are a type of motor frequently used when precise rotations are required. In a stepper motor an internal rotor containing PMs or a magnetically soft rotor with salient poles is controlled by a set of external magnets that are switched electronically. A stepper motor may also be thought of as a cross between a DC electric motor and a rotary solenoid. As each coil is energized in turn, the rotor aligns itself with the magnetic field produced by the energized field winding. Unlike a synchronous motor, in its application, the stepper motor may not rotate continuously; instead, it "steps"starts and then quickly stops againfrom one position to the next as field windings are energized and de-energized in sequence. Depending on the sequence, the rotor may turn forwards or backwards, and it may change direction, stop, speed up or slow down arbitrarily at any time.
When are stepper motors most useful?
A:
when precise rotations are required