Exercícios Propostos cap.6:
6.1 / 6.3 / 6.7 / 6.8 / 6.10 /6.12 / 6.15 /
6.16 / 6.21 / 6.22 /6.24/ 6.27 / 6.29 /
6.31 / 6.34 6.33/ 6.35 /6.40/ 6.42