6-31 In Fig. 6-41, solve for $R_t$, $I_t$, $V_1$, $V_2$, $V_3$, $V_4$, $V_5$, $V_6$, $I_2$, $I_3$, $I_4$ and $I_5$.
Figure 6-41
$V_t$
$R_1 = 180 \Omega$
$R_3 = 150 \Omega$
$R_6 = 220 \Omega$
$R_2 = 1.2 k\Omega$
$R_4 = 330 \Omega$
$R_5 = 120 \Omega$
$P_5 = 48 mW