7. 1c#, 1::1B22217<141DBB3<1@15mma<1@12 <1a51 ª5<1@1<1-a'-m<1 5), p.51

$. 1d, %1?+1::1B2221B<1DBB3<1@1)**o<1@1<15i5, pp.5-5