1.  I would invent a wormhole generator and some sort of ship that would be able to withstand the travel through space and time.  It would probably be bulky because it is a Mk 1.  I don't know exactly how it would function because if it did then I would already be building it.  But it would generate a wormhole to (hopefully) a specific position in the galaxy.  This could benefit the human race by allowing us to leave our world and expand the human empire.  Colonizing other planets could boost science and create millions of jobs.  It would also solve overpopulation and food shortages given enough time.  However, this technology would inevitably lead towards wars that fight over planets and certain resource rich places.  But, that happens anyways here on Earth, so no big deal.

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