QUES: However, the lifecycles of most living polychaetes, which are almost all marine animals, are unknown, and only about 25% of the 300+ species whose lifecycles are known follow this pattern. About 14% use a similar external fertilization but produce yolk-rich eggs, which reduce the time the larva needs to spend among the plankton, or eggs from which miniature adults emerge rather than larvae. The rest care for the fertilized eggs until they hatch some by producing jelly-covered masses of eggs which they tend, some by attaching the eggs to their bodies and a few species by keeping the eggs within their bodies until they hatch. These species use a variety of methods for sperm transfer; for example, in some the females collect sperm released into the water, while in others the males have a penis that inject sperm into the female. There is no guarantee that this is a representative sample of polychaetes' reproductive patterns, and it simply reflects scientists' current knowledge.

What are all polychaetes' eggs covered in?
What is the answer?
ANS: unanswerable
QUES: Although the United States has no de jure official language, English is the dominant language of business, education, government, religion, media, culture, civil society, and the public sphere. Virtually all state and federal government agencies and large corporations use English as their internal working language, especially at the management level. Some states, such as New Mexico, provide bilingual legislated notices and official documents, in Spanish and English, and other commonly used languages. By 2015, there was a trend that most Americans and American residents who are of Hispanic descent speak only English in the home.

Is there an official language of the United States?
What is the answer?
ANS: United States has no de jure official language, English is the dominant language
QUES: One wave of the population boom ended abruptly in the mid-1980s, as oil prices fell precipitously. The space industry also suffered in 1986 after the Space Shuttle Challenger disintegrated shortly after launch. There was a cutback in some activities for a period. In the late 1980s, the city's economy suffered from the nationwide recession. After the early 1990s recession, Houston made efforts to diversify its economy by focusing on aerospace and health care/biotechnology, and reduced its dependence on the petroleum industry. Since the increase of oil prices in the 2000s, the petroleum industry has again increased its share of the local economy.

What did Houston focus on after the 1990s recession to improve its economy?
What is the answer?
ANS:
aerospace and health care