Tolong di jawab pakai cara ya

1)L=3,14×20×20
=314×4=1256cm²
K=3,14×40=125,6cm
2)L=3,14×15/2×15/2=171
K=3,14×15=47,4
3)200-100:(4×5)+5
=200-(100:20)+5
=200-5+5=190
4)61+27=98
5)V=10×15×3=450:1/4
=112,5aaf kaau salah