tolong bantu ya,yang no 4 dan 5 beserta Caranya!!...besok dikumpulin.

4. L1 = p x l = 35 cm x 20 = 700 cm2
L2 = 1/2 x phi x r2 = 1/2 x 3,14 x 10 x 10 = 157 cm2
L3 = L2 = 157 cm2
Luas daerah di arsir = 700- (157+157)
= 700 - 314 = 386 cm2

5. L1 = p x l = 12 x 6 = 72 cm2
L2 = a x t = 8 x 5 = 40 cm2
L3 = 1/2 x a x t = 1/2 x 4 x 5 = 10cm
Luas total = 72 + 40 + 10 = 122 cm2