13.37 Language Proof and Logic

This is done on the program Fitch and I dont really know how to solve it.

Here it is:

x (Dodec(x) LeftOf(x, a))

x (Tet(x) RightOf(x, a))

x y (LeftOf(x, y) SameCol(x, y))

x y (RightOf(x, y) SameCol(x, y))

x (Cube(x) Dodec(x) Tet(x))

And prove this:

x (SameCol(x, a) Cube(x))