Atebodd y Dirprwy Weinidog Tai Joyce Watson AC nifer o gwestiynau am newidiadau arfaethedig llywodraeth glymblaid y DU i'r system budd-daliadau tai ar 2 Chwefror 2011.

BBC: Cwestiynau cynaliadwyedd

The knobs are connected to a pulley system, which moves a brass stylus along an X-Y axis.

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