tolong bantu yg no. 15 ya, buat besok *pake cara

5 x panjang busur = keliling lingkaran
5 x 6,28 = π x d
5 x 6,28 = 3,14 x d
31,4 = 3,14 x d
d = 31,4 : 3,14
d = 10 cm

r = 10 : 2
r = 5 cm

Volume kerucut = ⅓ x π x r² x t = ⅓ x 3,14 x 5 x 5 x 15 = 392,5 cm³