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Problem 4. Earth is at the origin (0,0), the moon is at (384,0), and a spaceship is at

(280,90) (where distance is in thousands of kilometers).

(a) What is the displacement vector of the moon relative to Earth? Of the spaceship

relative to Earth? Of the spaceship relative to the moon?

(b) How far is the spaceship from the earth? From the moon?

(c) The gravitational force on the spaceship from the earth is 461 newtons, and from the

moon is 26 newtons. What is the net gravitational force on the spaceship?