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Mastic asphalt is a type of asphalt which differs from dense graded asphalt (asphalt concrete) in that it has a higher asphalt/bitumen (binder) content, usually around 710% of the whole aggregate mix, as opposed to rolled asphalt concrete, which has only around 5% added asphalt/bitumen. This thermoplastic substance is widely used in the building industry for waterproofing flat roofs and tanking underground. Mastic asphalt is heated to a temperature of 210 C (410 F) and is spread in layers to form an impervious barrier about 20 millimeters (0.79 inches) thick.
What percentage of concrete is in mastic asphalt?
A: unanswerable

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With high cost of labor in developed countries, production automation has become increasingly popular. Rather than being assembled by hand, mosaics designed using computer aided design (CAD) software can be assembled by a robot. Production can be greater than 10 times faster with higher accuracy. But these "computer" mosaics have a different look than hand-made "artisanal" mosaics. With robotic production, colored tiles are loaded into buffers, and then the robot picks and places tiles individually according to a command file from the design software.
How does the robot pick the tiles it places?
A: a command file

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Besides the fibres, pulps may contain fillers such as chalk or china clay, which improve its characteristics for printing or writing. Additives for sizing purposes may be mixed with it and/or applied to the paper web later in the manufacturing process; the purpose of such sizing is to establish the correct level of surface absorbency to suit ink or paint.
Pulps only contain fibers and never what?
A: unanswerable

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In terms of school casualties, thousands of school children died due to shoddy construction. In Mianyang City, seven schools collapsed, burying at least 1,700 people. At least 7,000 school buildings throughout the province collapsed. Another 700 students were buried in a school in Hanwang. At least 600 students and staff died at Juyuan Elementary School. Up to 1,300 children and teachers died at Beichuan Middle School.
How many students were buried in a school in Hanwang?
A:
700