In this task, you are given a question and a context passage. You have to answer the question based on the given passage.

Input: Consider Input: 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".

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

Input: Consider Input: How was access gained to Alaska, Context: The specifics of Paleo-Indian migration to and throughout the Americas, including the exact dates and routes traveled, provide the subject of ongoing research and discussion. According to archaeological and genetic evidence, North and South America were the last continents in the world with human habitation. During the Wisconsin glaciation, 5017,000 years ago, falling sea levels allowed people to move across the land bridge of Beringia that joined Siberia to north west North America (Alaska). Alaska was a glacial refugia because it had low snowfall, allowing a small population to exist. The Laurentide Ice Sheet covered most of North America, blocking nomadic inhabitants and confining them to Alaska (East Beringia) for thousands of years.

Output: the land bridge

Input: Consider Input: Bush competed with someone from?, Context: Bush focused his campaign on national security, presenting himself as a decisive leader and contrasted Kerry as a "flip-flopper." This strategy was designed to convey to American voters the idea that Bush could be trusted to be tough on terrorism while Kerry would be "uncertain in the face of danger." Bush (just as his father did with Dukakis in the 1988 election) also sought to portray Kerry as a "Massachusetts liberal" who was out of touch with mainstream Americans. One of Kerry's slogans was "Stronger at home, respected in the world." This advanced the suggestion that Kerry would pay more attention to domestic concerns; it also encapsulated Kerry's contention that Bush had alienated American allies by his foreign policy.
Output: Massachusetts