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Aregion of space in which a measurable gravitational force is indicated by the force exerted on a test mass is called

Two students, each riding bicycles, start from the same apartment building and ride to the same building on campus, but each takes a different route. the first student rides 1100 m due east and then turns due north and travels another 1430 m before arriving at the destination. the second student heads due north for 1930 m and then turns and heads directly toward the destination.at the turning point, how far is the second student from the destination?

How many neutrons does plutonium -196 with an atomic number of 78.