$1)$ How large is the potential at point C

$2)$ Determine the power in the voltage source V$1$

$3)$ Is the source V$1$ generating power or consuming power? Please give reasons for your answer.

$4)$ What is R$3$ voltage $($U$3)$ depending on calculation wise, and how to know if the current sources I$2$ and I$3$ have same voltage drop just by looking at them? No calculations needed