tolong jawab nomer 18 dan 19

18) s = 10 km
t = 06.45 - 05.30 = 01.15 = 1¼ jam
v = s ÷ t
= 10 km ÷ 1¼ jam
= 10 ÷ 5/4
= 10 × 4/5
= 8 km/jam ( A )

19) 0,28 m³ + 180 dm³ - 34 liter
= ( 0,28 × 1000) + 180 - 34
= 280 + 180 - 34
= 426 liter ( D )