This task is about reading the given passage and construct a question about the information present in the passage. Construct a question in such a way that (i) it is unambiguous, (ii) it is answerable from the passage, (iii) its answer is unique (iv) its answer is a continuous text span from the paragraph. Avoid creating questions that (i) can be answered correctly without actually understanding the paragraph and (ii) uses same words or phrases given in the passage.

In Western societies, skirts, dresses and high-heeled shoes are usually seen as women's clothing, while neckties are usually seen as men's clothing. Trousers were once seen as exclusively male clothing, but are nowadays worn by both genders. Male clothes are often more practical (that is, they can function well under a wide variety of situations), but a wider range of clothing styles are available for females. Males are typically allowed to bare their chests in a greater variety of public places. It is generally acceptable for a woman to wear traditionally male clothing, while the converse is unusual.
What is an example of clothing that was once seen as exclusively for males?

In September 2003, a new type of blue LED was demonstrated by Cree that consumes 24 mW at 20 milliamperes (mA). This produced a commercially packaged white light giving 65 lm/W at 20 mA, becoming the brightest white LED commercially available at the time, and more than four times as efficient as standard incandescents. In 2006, they demonstrated a prototype with a record white LED luminous efficacy of 131 lm/W at 20 mA. Nichia Corporation has developed a white LED with luminous efficacy of 150 lm/W at a forward current of 20 mA. Cree's XLamp XM-L LEDs, commercially available in 2011, produce 100 lm/W at their full power of 10 W, and up to 160 lm/W at around 2 W input power. In 2012, Cree announced a white LED giving 254 lm/W, and 303 lm/W in March 2014. Practical general lighting needs high-power LEDs, of one watt or more. Typical operating currents for such devices begin at 350 mA.
In what year was a new type of blue LED produced?

Germany is a federal republic consisting of sixteen federal states (German: Bundesland, or Land).[a] Since today's Germany was formed from an earlier collection of several states, it has a federal constitution, and the constituent states retain a measure of sovereignty. With an emphasis on geographical conditions, Berlin and Hamburg are frequently called Stadtstaaten (city-states), as is the Free Hanseatic City of Bremen, which in fact includes the cities of Bremen and Bremerhaven. The remaining 13 states are called Flächenländer (literally: area states).

How many federal states does Germany have?