Answer:
Explanation:
Power in the circuit must balance
Voltages about any loop must add to zero
Current through any node must add to zero
p1 has 5V and 8 Amps leaving the + terminal
This means that (5)(8) = 40 W is being supplied by p1 ergo -40W
p2 has 2V and 8 amps entering the + terminal
2(8) = 16 W absorbed by p2
p4 has 3V and 5 amps entering the + terminal
3(5) = 15 W absorbed by p4
Balance of power shows that p3 must absorb
15 + 16 + P3 - 40 = 0
P3 = 9 W absorbed