In this task, you are given a question and a context passage. You have to answer the question based on the given passage.
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Question: It became easier to move around in non-deep water thanks to what living entity?, Context: The tide-predicting machine invented by Sir William Thomson in 1872 was of great utility to navigation in shallow waters. It used a system of pulleys and wires to automatically calculate predicted tide levels for a set period at a particular location.

Answer: Sir William Thomson


Question: What was Cork City formerly surrounded by?, Context: The city's charter was granted by Prince John, as Lord of Ireland, in 1185. The city was once fully walled, and some wall sections and gates remain today. For much of the Middle Ages, Cork city was an outpost of Old English culture in the midst of a predominantly hostile Gaelic countryside and cut off from the English government in the Pale around Dublin. Neighbouring Gaelic and Hiberno-Norman lords extorted "Black Rent" from the citizens to keep them from attacking the city. The present extent of the city has exceeded the medieval boundaries of the Barony of Cork City; it now takes in much of the neighbouring Barony of Cork. Together, these baronies are located between the Barony of Barrymore to the east, Muskerry East to the west and Kerrycurrihy to the south.

Answer: wall


Question: What broadcast system does not cause a perceptible speedup when broadcasting 24 frames per second film content?, Context: Standard 35mm photographic film used for cinema projection has a much higher image resolution than HDTV systems, and is exposed and projected at a rate of 24 frames per second (frame/s). To be shown on standard television, in PAL-system countries, cinema film is scanned at the TV rate of 25 frame/s, causing a speedup of 4.1 percent, which is generally considered acceptable. In NTSC-system countries, the TV scan rate of 30 frame/s would cause a perceptible speedup if the same were attempted, and the necessary correction is performed by a technique called 3:2 Pulldown: Over each successive pair of film frames, one is held for three video fields (1/20 of a second) and the next is held for two video fields (1/30 of a second), giving a total time for the two frames of 1/12 of a second and thus achieving the correct average film frame rate.

Answer:
PAL