maaf kalau soal gini

1.
Volume tabung :
V = phi x r x r x t
= 22/7 x 3,5 x 3,5 x 20
= 770 cm.

Luas permukaan balok :
L = 2 x (P+L) + 2 x (P+T) + 2 x (L+T)
= 2 x (30+20) + 2 x (30+22) + 2 x (20+22)
= 2 x 50 + 2 x 52 + 2 x 42
= 100 + 104 + 84
= 288 cm.

Total :
= Volume Tabung + Luas Permukaan Balok
= 770 + 288 cm
= 1.058 cm.

2.
Volume Prisma Tegak Segitiga :
V = 1/2 x 10 x 12 x 8
= 1/2 x 120 x 8
= 1/2 x 960
= 480 cm

Luas alas :
L = 1/2 x 10 x 8
= 1/2 x 80
= 40 cm

Luas Permukaan Prisma Tegak Segitiga :
L = 2 x luas alas + 3 x p x l
= 2 x 40 + 3 x 12 x 8
= 80 + 288
= 368 cm.