one for A,B,C,R1,R3 and one for R2.
Why I have merged them bcoz B and C participate totaly with one to one particapation in R3. Hence can be merged giving BC.
Now BC participates totally with one to one particapation in R1 with A. Hence can be merged -->ABC
R2 is m:n ---> Needs a separate table.
At end we have ABC entity set having a self relationship of cardinality m:n.