Extract the answer to the question from the following context. Question: What does PCR do to things which infect other things? Context: Thus, the technological ability to detect any infectious agent rapidly and specifically are currently available. The only remaining blockades to the use of PCR as a standard tool of diagnosis are in its cost and application, neither of which is insurmountable. The diagnosis of a few diseases will not benefit from the development of PCR methods, such as some of the clostridial diseases (tetanus and botulism). These diseases are fundamentally biological poisonings by relatively small numbers of infectious bacteria that produce extremely potent neurotoxins. A significant proliferation of the infectious agent does not occur, this limits the ability of PCR to detect the presence of any bacteria.
----
Answer: detect

Extract the answer to the question from the following context. Question: How did Bell get the patent, according Wilber? Context: The patent examiner, Zenas Fisk Wilber, later stated in an affidavit that he was an alcoholic who was much in debt to Bell's lawyer, Marcellus Bailey, with whom he had served in the Civil War. He claimed he showed Gray's patent caveat to Bailey. Wilber also claimed (after Bell arrived in Washington D.C. from Boston) that he showed Gray's caveat to Bell and that Bell paid him $100. Bell claimed they discussed the patent only in general terms, although in a letter to Gray, Bell admitted that he learned some of the technical details. Bell denied in an affidavit that he ever gave Wilber any money.
----
Answer: He claimed he showed Gray's patent caveat to Bailey

Extract the answer to the question from the following context. Question: Airplanes have how many forms of suction? Context: Manifold vacuum can be used to drive accessories on automobiles. The best-known application is the vacuum servo, used to provide power assistance for the brakes. Obsolete applications include vacuum-driven windscreen wipers and Autovac fuel pumps. Some aircraft instruments (Attitude Indicator (AI) and the Heading Indicator (HI)) are typically vacuum-powered, as protection against loss of all (electrically powered) instruments, since early aircraft often did not have electrical systems, and since there are two readily available sources of vacuum on a moving aircraftthe engine and an external venturi. Vacuum induction melting uses electromagnetic induction within a vacuum.
----
Answer:
two readily available sources of vacuum