You are given a passage. You need to construct a question about the information present in the passage. Construct a question in such a way that (i) it is unambiguous, (ii) its answer is the whole paragraph. Avoid creating questions that can be answered correctly without actually understanding the paragraph.

110 Volts is nominal and may vary when measured by a voltmeter.  That said, power is supplied using sets of three separate parallel wires that you can see up on most power poles.  The very high voltage there is stepped down using a transformer to supply most houses and businesses with a usable lower voltage.  The voltage between any one of the three wires to ground in a house is 110 Volts for example to light a light bulb.  The voltage between any two wires is 220 Volts and is used for example to power a clothes dryer or kitchen range.  Houses do not use all three wires.  A machine shop may power a large motor by connecting all three wires (in a delta or Y configuration) to obtain 440 Volts.  Therefore the progression of 110, 220, and 440 Volts stems from the use of single, two and three-phase wiring circuits.  Electrical power is conducted cross-country at very high voltages using high tension lines strung in sets of three wires or phases which produces the multiple of 11 you mention.  Incidentally there may be an additional single wire above all the rest to arrest lightning strikes.
Why is the voltage ratinging always a multiple of 11 ?

It isn't as foggy as you might think. Spring and Fall are quite temperate, and San Francisco is renowned for it's "Indian Summer" in September. However, Mark Twain had a point when he said "The coldest Winter I ever spent was Summer in San Francisco."\nThis is because the warm air from inland (where it gets quite hot in the Summer) clashes with the cold air from the surrounding Pacific Ocean and the SF Bay. When that happens, fog forms. Further explanation from http://kids.earth.nasa.gov: "At night, the ground surface cools by radiating heat to space. Air near the ground cools to the dew point temperature, causing water in the air to condense."\nSure it's cold, but fog can be quite beautiful and atmospheric. Just look at the pictures on http://www.goldengatephoto.com/sanfran/thefogrollsin.html  Lovely!
Why is it so foggy in San Francisco?

Yeah paperairplane.com  is pretty resourceful... Specially for all you chocolate lovers....

how do u make a good paper airplane?

