First two are a bit hard to tell you at that size, 3rd is acropora carduus maybe? last one looks to be a very unhappy acropora lokani.
From the state of these pictured corals, you might have some issues going on. They don't look very happy in the pics.
EDIT: Again frags are hard to tell, but looking closer, Id risk a guess that #2 is acropora anthocercis.
Maybe start a new thread below in the SPS section with full parameters and system details so we can help you make these start thriving. Acros can be tricky!