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28 November 2009
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Cymraeg
Mathemateg
Ffiseg
Cemeg
Bioleg
Welsh second language
hafan
/
bioleg
/
Prosesau Bywyd a Gweithgarwch Celloedd
Bodau Dynol fel Organebau
Planhigion Gwyrdd fel Organebau
Etifeddiad ac Amrywiad
Pethau Byw yn eu Hamgylchedd
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