tolong di bantu ya pake cara

36. A) Busur AB = 90°/360° x π x d
= 1/4 x 3,14 x 20 cm
= 3,14 x 5 cm
= 15,7 cm
B) L AOB = 90°/360° x π x r²
= 1/4 x 3,14 x (10 cm)²
= 1/4 x 3,14 x 100 cm²
= 78,5 cm²

40. A) V balok = p.l.t
= 20 cm x 10 cm x 5 cm
= 1000 cm²
B) L permukaan = 2((p.l)+(p.t)+(l.t))
= 2 ((20.10)+(20.5)+(10.5))
= 2 (200+100+50) = 2(350)
= 700 cm²