9.} "IS pts.| in the circuit below. assume that SWI and SW2 is closed {connected} |Note: the diagram below shows the switches in the open position. But assume they are closed for this problem]. Use the generalized concept of a voltage divider [review your notesi'lecture slides] to nd expressions for the voltage V1 and v4 in the circuit below. Your expression should be in terms of Us and illRd. R1 Note: V3 is the voltage across the series of SWI and R3 Note: V4 is the voltage across the series of SW2 and R4 Ill] [ti pts.| Look at the circuit from problem 9 and reuse the equation you found. lfSW2 is now open {not connected] but SW1 is still closed {connected} derive an expression for V4 [voltage across SW2 and R4}? 1|t'our expression should be in terms of Us and {possibly} some oleRl. Hint: Remember a switch can be modeled as either a VERY LARGE {innite} resistance or VER'I' SMALL {zero} resistance. With SW2 open, what resistance value can be used to model the ellect of SW2 and R4