<span>Trigonometry (from Greek trigōnon, "triangle" and metron, "measure") is a branch of mathematics that studies relationships involving lengths and angles of triangles. The field emerged in the Hellenistic world during the 3rd century BC from applications of geometry to astronomical studies
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Answer:
D. Renounce your citizenship
Explanation:
To become an expatriate, is to renounce your citizenship. Example: A man renounces his citizenship from Canada. He is now an expat.
