Have answers for last few but cannot explain answers .Help please and thanks.
30a Pull up there's an obstruction (5) - - T- H. HITCH? but why?
35d.I dropped fromhigh position into lake below. (4). E- R _. EIRE?? but why
17d. Train staf fbefore becoming internatinal business people(9).. EXPORTERS?, but cannot work out wordplay