Problem: Using histological stains on expectorated samples from phlegm (also called "sputum"), scientists can identify MTB under a microscope. Since MTB retains certain stains even after being treated with acidic solution, it is classified as an acid-fast bacillus. The most common acid-fast staining techniques are the ZiehlNeelsen stain and the Kinyoun stain, which dye acid-fast bacilli a bright red that stands out against a blue background. Auramine-rhodamine staining and fluorescence microscopy are also used.
What is another name for an expectorated sample?
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Answer: unanswerable

Problem: Airport construction boomed during the 1960s with the increase in jet aircraft traffic. Runways were extended out to 3,000 m (9,800 ft). The fields were constructed out of reinforced concrete using a slip-form machine that produces a continual slab with no disruptions along the length. The early 1960s also saw the introduction of jet bridge systems to modern airport terminals, an innovation which eliminated outdoor passenger boarding. These systems became commonplace in the United States by the 1970s.
What were jet bridge systems made of?
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Answer: unanswerable

Problem: Media outlets began reporting in late September 2009 that Comcast was in talks to buy NBCUniversal. Comcast denied the rumors at first, while NBC would not comment on them. However, CNBC itself reported on October 1 that General Electric was considering spinning NBCUniversal off into a separate company that would merge the NBC television network and its cable properties such as USA Network, Syfy and MSNBC with Comcast's content assets. GE would maintain 49% control of the new company, while Comcast owned 51%. Vivendi, which owns 20%, would have to sell its stake to GE. It was reported that under the current deal with GE that it would happen in November or December. It was also reported that Time Warner would be interested in placing a bid, until CEO Jeffrey L. Bewkes directly denied interest, leaving Comcast the sole bidder. On November 1, 2009, The New York Times reported Comcast had moved closer to a deal to purchase NBCUniversal and that a formal announcement could be made sometime the following week.
When did CNBC announce Comcast had bought NBCUniversal?
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Answer:
unanswerable