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Adrodd fel Amhriodol

Testun Gwreiddiol (Anodiad: EAW041940 / 1437529)

' Several balloons were flown in the early 1950s to test wind speeds when planning construction of the BBC TV mast. '

Dywedwch wrthym pam mae’r cynnwys hwn yn amhriodol *(gofynnol)

Dewis categori *(gofynnol)

Os ‘Arall’ rhowch fanylion (dewisol)

Eich enw (dewisol)

Eich cyfeiriad e-bost (dewisol)

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