tolong cari luas nya

Dik : r = 1/2 10 = 5cm
t = 50cm
Dit : L...?
Penye : L = 2 Π r (r +t)
L = 2 x 3,14 x 5 ( 5 + 50 )
L = 31,4 ( 55)
L = 1727 cm^2


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