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: What is the force of gravity noted as?, Context: Since then, and so far, general relativity has been acknowledged as the theory that best explains gravity. In GR, gravitation is not viewed as a force, but rather, objects moving freely in gravitational fields travel under their own inertia in straight lines through curved space-time – defined as the shortest space-time path between two space-time events. From the perspective of the object, all motion occurs as if there were no gravitation whatsoever. It is only when observing the motion in a global sense that the curvature of space-time can be observed and the force is inferred from the object's curved path. Thus, the straight line path in space-time is seen as a curved line in space, and it is called the ballistic trajectory of the object. For example, a basketball thrown from the ground moves in a parabola, as it is in a uniform gravitational field. Its space-time trajectory (when the extra ct dimension is added) is almost a straight line, slightly curved (with the radius of curvature of the order of few light-years). The time derivative of the changing momentum of the object is what we label as "gravitational force".

Answer: The time derivative of the changing momentum of the object


Question: What vehicle could you have that you would need lower pressure boiler feed water?, Context: The Rankine cycle and most practical steam engines have a water pump to recycle or top up the boiler water, so that they may be run continuously. Utility and industrial boilers commonly use multi-stage centrifugal pumps; however, other types are used. Another means of supplying lower-pressure boiler feed water is an injector, which uses a steam jet usually supplied from the boiler. Injectors became popular in the 1850s but are no longer widely used, except in applications such as steam locomotives.

Answer: steam locomotives


Question: The French flag includes red because it is what?, Context: Red is one of the most common colors used on national flags. The use of red has similar connotations from country to country: the blood, sacrifice, and courage of those who defended their country; the sun and the hope and warmth it brings; and the sacrifice of Christ's blood (in some historically Christian nations) are a few examples. Red is the color of the flags of several countries that once belonged to the former British Empire. The British flag bears the colors red, white, and blue; it includes the cross of Saint George, patron saint of England, and the saltire of Saint Patrick, patron saint of Ireland, both of which are red on white. The flag of the United States bears the colors of Britain, the colors of the French tricolore include red as part of the old Paris coat of arms, and other countries' flags, such as those of Australia, New Zealand, and Fiji, carry a small inset of the British flag in memory of their ties to that country. Many former colonies of Spain, such as Mexico, Colombia, Ecuador, Cuba, Puerto Rico, Peru, and Venezuela, also feature red-one of the colors of the Spanish flag-on their own banners. Red flags are also used to symbolize storms, bad water conditions, and many other dangers. Navy flags are often red and yellow. Red is prominently featured in the flag of the United States Marine Corps.

Answer:
part of the old Paris coat of arms