Exercise 19
Calculate the voltage drop on each resistor and indicate the polarity of
the voltage drop on each resistor with the switch open, as indicated.
Next, calculate the voltage drop on each resistor and indicate the polarity
of the voltage drop on each resistor when the switch is closed.

Given:
Vb1 = 7V
Vb2 = 3V
R1 = 10K ohm
R2 = 5K ohm
R3 = 20K ohm
R4 = 15K ohm
​