tolong pake cara yaaaaaa

28. luas permukaan = 6 x s x s = 6 x 18 x 18 = 1944 cm²

29. v = 1/4 x 3,14 x 30 x 30 x 40 = 314 x 10 x 9= 28.260 cm³

30. volume kubus = s³= 16³= 4096 cm³
volume prisma = 1/2 x 16 x 10 x 16
= 80 x 16= 1280
volume = 28.260 + 1280= 5376 cm³