Itjustmaybetheworld’smostcostlyvacuumcleaner(吸尘器).Thepr...
问题详情：Itjustmaybetheworld’smostcostlyvacuumcleaner(吸尘器).ThepriceofCleanSpaceOneiselevenmilliondollars.Butyet,ithasabigjobtodo.Recently,researchersinSwitzerlandsaidtheyplannedtobuildthisnewcleani...