In this task, you are given a question and a context passage. You have to answer the question based on the given passage.

[EX Q]: Waves contain?, Context: As an electro-magnetic wave travels through the different parts of the antenna system (radio, feed line, antenna, free space) it may encounter differences in impedance (E/H, V/I, etc.). At each interface, depending on the impedance match, some fraction of the wave's energy will reflect back to the source, forming a standing wave in the feed line. The ratio of maximum power to minimum power in the wave can be measured and is called the standing wave ratio (SWR). A SWR of 1:1 is ideal. A SWR of 1.5:1 is considered to be marginally acceptable in low power applications where power loss is more critical, although an SWR as high as 6:1 may still be usable with the right equipment. Minimizing impedance differences at each interface (impedance matching) will reduce SWR and maximize power transfer through each part of the antenna system.
[EX A]: power

[EX Q]: Which artist is listed  first, Context: Similarly, movies and television often revert to standard, clichéd snatches of classical music to convey refinement or opulence: some of the most-often heard pieces in this category include Bach´s Cello Suite No. 1, Mozart's Eine kleine Nachtmusik, Vivaldi's Four Seasons, Mussorgsky's Night on Bald Mountain (as orchestrated by Rimsky-Korsakov), and Rossini's William Tell Overture.
[EX A]: Bach

[EX Q]: A plant that only sprouts flowers once a year is described as?, Context: The Judicial Council is the highest court in the denomination. It consists of nine members, both laity and clergy, elected by the General Conference for an eight-year term. The ratio of laity to clergy alternates every eight years. The Judicial Council interprets the Book of Discipline between sessions of General Conference, and during General Conference, the Judicial Council rules on the constitutionality of laws passed by General Conference. The Council also determines whether actions of local churches, annual conferences, church agencies, and bishops are in accordance with church law. The Council reviews all decisions of law made by bishops The Judicial Council cannot create any legislation; it can only interpret existing legislation. The Council meets twice a year at various locations throughout the world. The Judicial Council also hears appeals from those who have been accused of chargeable offenses that can result in defrocking or revocation of membership.
[EX A]:
annual