Bantu yaaa tolong cepet hehehhe

18)
V tabung = L alas x T
1.100 = πr² x T
1.100 = 22/7 (5²) x T
1.100 = 550/7 x T
T = 1.100 : 550/7
T = 1.100 x 7/550
T = 14 cm (C)

19)
d = 12 → r = 6 cm
Luas sisi tabung tertutup :
= 2πr (r + t)
= 2 . (3,14) . 6 (6 + 8)
= 37,68 (14)
= 527,52 cm²
≈ 528 cm² (A)

20)
d = 20 → r = 10
V kerucut
= 1/3πr²t
= 1/3 (3,14) (10²) (15)
= 1570 cm³ (A)