Question: There are several types of multi-color white LEDs: di-, tri-, and tetrachromatic white LEDs. Several key factors that play among these different methods, include color stability, color rendering capability, and luminous efficacy. Often, higher efficiency will mean lower color rendering, presenting a trade-off between the luminous efficacy and color rendering. For example, the dichromatic white LEDs have the best luminous efficacy (120 lm/W), but the lowest color rendering capability. However, although tetrachromatic white LEDs have excellent color rendering capability, they often have poor luminous efficacy. Trichromatic white LEDs are in between, having both good luminous efficacy (>70 lm/W) and fair color rendering capability.
Is there an answer to this question: What luminous efficacy does non-trichromatic white LEDs have?

Answer: unanswerable

Question: In almost all federations the central government enjoys the powers of foreign policy and national defense as exclusive federal powers. Were this not the case a federation would not be a single sovereign state, per the UN definition. Notably, the states of Germany retain the right to act on their own behalf at an international level, a condition originally granted in exchange for the Kingdom of Bavaria's agreement to join the German Empire in 1871. Beyond this the precise division of power varies from one nation to another. The constitutions of Germany and the United States provide that all powers not specifically granted to the federal government are retained by the states. The Constitution of some countries like Canada and India, on the other hand, state that powers not explicitly granted to the provincial governments are retained by the federal government. Much like the US system, the Australian Constitution allocates to the Federal government (the Commonwealth of Australia) the power to make laws about certain specified matters which were considered too difficult for the States to manage, so that the States retain all other areas of responsibility. Under the division of powers of the European Union in the Lisbon Treaty, powers which are not either exclusively of European competence or shared between EU and state as concurrent powers are retained by the constituent states.
Is there an answer to this question: In nearly all federalism countries, central powers enjoy what?

Answer: the powers of foreign policy and national defense as exclusive federal powers

Question: The early Christian philosophy of Augustine of Hippo was heavily influenced by Plato. A key change brought about by Christian thought was the moderatation of the Stoicism and theory of justice of the Roman world, as well emphasis on the role of the state in applying mercy as a moral example. Augustine also preached that one was not a member of his or her city, but was either a citizen of the City of God (Civitas Dei) or the City of Man (Civitas Terrena). Augustine's City of God is an influential work of this period that attacked the thesis, held by many Christian Romans, that the Christian view could be realized on Earth.
Is there an answer to this question: Who taught that one was a member of their city?

Answer: unanswerable

Question: The Raleigh Parks and Recreation Department offers a wide variety of leisure opportunities at more than 150 sites throughout the city, which include: 8,100 acres (33 km2) of park land, 78 miles (126 km) of greenway, 22 community centers, a BMX championship-caliber race track, 112 tennis courts among 25 locations, 5 public lakes, and 8 public aquatic facilities. The J. C. Raulston Arboretum, an 8-acre (32,000 m) arboretum and botanical garden in west Raleigh administered by North Carolina State University, maintains a year-round collection that is open daily to the public without charge.
Is there an answer to this question: What is the 10-acre arboretum called?

Answer:
unanswerable