Problem: The currentvoltage characteristic of an LED is similar to other diodes, in that the current is dependent exponentially on the voltage (see Shockley diode equation). This means that a small change in voltage can cause a large change in current. If the applied voltage exceeds the LED's forward voltage drop by a small amount, the current rating may be exceeded by a large amount, potentially damaging or destroying the LED. The typical solution is to use constant-current power supplies to keep the current below the LED's maximum current rating. Since most common power sources (batteries, mains) are constant-voltage sources, most LED fixtures must include a power converter, at least a current-limiting resistor. However, the high resistance of three-volt coin cells combined with the high differential resistance of nitride-based LEDs makes it possible to power such an LED from such a coin cell without an external resistor.
What feature do most LED fixtures need to have?
The answer is the following: a power converter

Problem: Next to sound shifts, there are ample examples of suffix differences. Often simple suffix shifts (like switching between -the, -ske, -ke, -je, ...), sometimes the suffixes even depend on quite specific grammar rules for a certain dialect. Again taking West Flemish as an example. In that language, the words "ja" (yes) and "nee" (no) are also conjugated to the (often implicit) subject of the sentence. These separate grammar rules are a lot more difficult to imitate correctly than simple sound shifts, making it easy to recognise people who didn't grow up in a certain region, even decades after they moved.
How would you tell a West Flemish speaker "yes"?
The answer is the following: ja

Problem: In the 1940s, Detroit blues artist John Lee Hooker became a long-term resident in the city's southwest Delray neighborhood. Hooker, among other important blues musicians migrated from his home in Mississippi bringing the Delta blues to northern cities like Detroit. Hooker recorded for Fortune Records, the biggest pre-Motown blues/soul label. During the 1950s, the city became a center for jazz, with stars performing in the Black Bottom neighborhood. Prominent emerging Jazz musicians of the 1960s included: trumpet player Donald Byrd who attended Cass Tech and performed with Art Blakey and the Jazz Messengers early in his career and Saxophonist Pepper Adams who enjoyed a solo career and accompanied Byrd on several albums. The Graystone International Jazz Museum documents jazz in Detroit.
Which musician accompanied Donald Byrd on several albums?
The answer is the following: Pepper Adams

Problem: At the age of 21 he settled in Paris. Thereafter, during the last 18 years of his life, he gave only some 30 public performances, preferring the more intimate atmosphere of the salon. He supported himself by selling his compositions and teaching piano, for which he was in high demand. Chopin formed a friendship with Franz Liszt and was admired by many of his musical contemporaries, including Robert Schumann. In 1835 he obtained French citizenship. After a failed engagement to Maria Wodzinska, from 1837 to 1847 he maintained an often troubled relationship with the French writer George Sand. A brief and unhappy visit to Majorca with Sand in 183839 was one of his most productive periods of composition. In his last years, he was financially supported by his admirer Jane Stirling, who also arranged for him to visit Scotland in 1848. Through most of his life, Chopin suffered from poor health. He died in Paris in 1849, probably of tuberculosis.
What was the likely cause of death for Chopin?
The answer is the following:
tuberculosis