kak kak tolong dijawab

23. Keliling lingakaran = 2×v×r
= 2×3.14×10
= 2×31.4
= 62.8 cm (B)

24. Luas 1/2 lingkaran = 1/2×v×r×r
= 1/2×22/7×42×42
= 2.772 cm persegi (B)