This task is about writing a correct answer for the reading comprehension task. Based on the information provided in a given passage, you should identify the shortest continuous text span from the passage that serves as an answer to the given question. Avoid answers that are incorrect or provides incomplete justification for the question.

[EX Q]: Passage: In the 16th century, Count Hieronymus Schlick of Bohemia began minting coins known as Joachimstalers (from German thal, or nowadays usually Tal, "valley", cognate with "dale" in English), named for Joachimstal, the valley where the silver was mined (St. Joachim's Valley, now Jachymov; then part of the Kingdom of Bohemia, now part of the Czech Republic). Joachimstaler was later shortened to the German Taler, a word that eventually found its way into Danish and Swedish as daler, Norwegian as dalar and daler, Dutch as daler or daalder, Ethiopian as (talari), Hungarian as taller, Italian as tallero, and English as dollar. Alternatively, thaler is said to come from the German coin Guldengroschen ("great guilder", being of silver but equal in value to a gold guilder), minted from the silver from Joachimsthal. Question: Other than "taler", what is the other name of the German coin?
[EX A]: Guldengroschen

[EX Q]: Passage: In the Romantic era, the modern piano, with a more powerful, sustained tone and a wider range took over from the more delicate-sounding fortepiano. In the orchestra, the existing Classical instruments and sections were retained (string section, woodwinds, brass and percussion), but these sections were typically expanded to make a fuller, bigger sound. For example, while a Baroque orchestra may have had two double bass players, a Romantic orchestra could have as many as ten. "As music grew more expressive, the standard orchestral palette just wasn't rich enough for many Romantic composers." New woodwind instruments were added, such as the contrabassoon, bass clarinet and piccolo and new percussion instruments were added, including xylophones, drums, celestes (a bell-like keyboard instrument), large orchestral harps, bells, and triangles and even wind machines for sound effects. Question: What is a celestes?
[EX A]: a bell-like keyboard instrument

[EX Q]: Passage: To prevent the risk of out-of-phase supplies mixing, sections of line fed from different feeder stations must be kept strictly isolated. This is achieved by Neutral Sections (also known as Phase Breaks), usually provided at feeder stations and midway between them although, typically, only half are in use at any time, the others being provided to allow a feeder station to be shut down and power provided from adjacent feeder stations. Neutral Sections usually consist of an earthed section of wire which is separated from the live wires on either side by insulating material, typically ceramic beads, designed so that the pantograph will smoothly run from one section to the other. The earthed section prevents an arc being drawn from one live section to the other, as the voltage difference may be higher than the normal system voltage if the live sections are on different phases and the protective circuit breakers may not be able to safely interrupt the considerable current that would flow. To prevent the risk of an arc being drawn across from one section of wire to earth, when passing through the neutral section, the train must be coasting and the circuit breakers must be open. In many cases, this is done manually by the drivers. To help them, a warning board is provided just before both the neutral section and an advance warning some distance before. A further board is then provided after the neutral section to tell drivers to re-close the circuit breaker, although drivers must not do this until the rear pantograph has passed this board. In the UK, a system known as Automatic Power Control (APC) automatically opens and closes the circuit breaker, this being achieved by using sets of permanent magnets alongside the track communicating with a detector on the train. The only action needed by the driver is to shut off power and coast and therefore warning boards are still provided at and on the approach to neutral sections. Question: What invention prevented lines from getting mixed?
[EX A]:
Phase Breaks