tolong dong nomer 1 Dan 2 3

1). V. tabung = phi × r2 × t
1540 = 22/7 × 7 × 7 ×t
40 = 7 × t
t = 40 ÷ 7
= 5, 71 cm

3). # V = 2744 dm3
# rusuk kubus/ tinggi tabung = akar 3 dari 2744
= 14 akar 14
= 14 dm
# d = 3/4 × 14
= 10, 5 dm

# r = 10, 5 ÷ 2
= 5, 25 dm

# V. tabung = phi × r2 × t
= 22/7 × 5, 25 × 5, 25 × 14
= 1212, 75 dm3