Nomor 18,19,20 Tolong dijawab ya besok dikumpul,please!!!

Yang saya bisa no 18=c ,20=d

[tex]a.1.2 \times 10000 + 7500 + 83 \times 100 + 0.9 \times 10000 \\ = 12000 + 7500 + 8300 + 9000\\ = 36800 {m}^{2} \\ b.30 \times 1 + 0.05 \times 1000 + 75 \times 1 \\ = 30 + 50 + 75 \\ = 155 {cm}^{3} \\ c.jarak \: = kecepatan \times waktu \\ = 40 \frac{km}{jam} \times 36menit \\ = \frac{40}{60} \frac{km}{menit} \times 36menit \\ = \frac{4}{6} \times 36 \\ = 4 \times 6 \\ = 24 \frac{km}{menit} \\ = 24km[/tex]