Which molecule has a trigonal planar shape? carbon monoxide boron trichloride silicon tetraiodide carbon tetrafluoride

This is actually very easy. Without drawing a single one of them I can tell that Boron Trichloride will be trigonal planar. Carbon monoxide is linear (It has two atoms), Silicon tetraiodide is either tetrahedral or more complex (depends on the actual amount of electron domains), and carbon tetrafluoride is tetrahedral. 

7is b8 is d9 is c10 is a11 is d