Here is a question about this article: Dumbwaiters are small freight elevators that are intended to carry food, books or other small freight loads rather than passengers. They often connect kitchens to rooms on other floors. they usually do not have the same safety features found in passenger elevators, like various ropes for redundancy. they have a lower capacity, and they can be up to 1 meter (3 ft.) tall. there's a control panel at every stop, that mimics the ones found in passenger elevators, like calling, door control, floor selection.
What is the answer to this question: What are small freight elevators used for things such as food, called?
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So... Dumbwaiters

Here is a question about this article: An exception is the United States, where patents filed prior to 8 June 1995 expire 17 years after the publication date of the patent, but application extensions make it possible for a patent to issue much later than normally expected (see submarine patents). The various MP3-related patents expire on dates ranging from 2007 to 2017 in the U.S. Patents filed for anything disclosed in ISO CD 11172 a year or more after its publication are questionable. If only the known MP3 patents filed by December 1992 are considered, then MP3 decoding has been patent-free in the US since 22 September 2015 when U.S. Patent 5,812,672 expired which had a PCT filing in October 1992. If the longest-running patent mentioned in the aforementioned references is taken as a measure, then the MP3 technology will be patent-free in the United States on 30 December 2017 when U.S. Patent 5,703,999, held by the Fraunhofer-Gesellschaft and administered by Technicolor, expires.
What is the answer to this question: What year is the latest that MP3 related patents will expire on in the United States?
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So... 2017

Here is a question about this article: During the First Opium War, the British navy defeated Eight Banners forces at Ningbo and Dinghai. Under the terms of the Treaty of Nanking, signed in 1843, Ningbo became one of the five Chinese treaty ports opened to virtually unrestricted foreign trade. Much of Zhejiang came under the control of the Taiping Heavenly Kingdom during the Taiping Rebellion, which resulted in a considerable loss of life in the province. In 1876, Wenzhou became Zhejiang's second treaty port.
What is the answer to this question: During which war did the British navy defeat Eight Banners forces at Ningbo and Dinghai?
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So...
the First Opium War