SOLUTION FOR Q2.
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A (A1,A2) PK : A1
H (H1, H2) PK : H1
A-H(A1,H1) PK : (A1,H1), FK A1 refs. A, FK H1 refs H
G (G1,G2,H1) PK: G1. FK: H1 refs H
BGH (B1,C1,H1,G1) PK: (B1,C1,H1,G1), FKs as above, plus B1, C1 ref B
FG (G1,C1) PK: (G1,C1), FK  G1 ref G(G1), C1 ref F(C1)
D (C1)  PK C1. FK  C1 refs C(C1). 
(this Entity Set can be deleted, is redundant)
E(C1,E1) C1 FK refs C(C1) PK : C1.
F(C1,F1) C1 FK refs C(C1) PK : C1.
B(B1,B2,C1,C11,A1) PK: (B1,C1). FK : C1 refs C(C1), C11 FK refs B(C1), A1 FK refs. A(A1)  
C(C1,C2) PK : C1