Is the source in parallel or series with the resistor?

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amg63
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Thank you for your time and effort. It is much appreciated.
1. Homework Statement

I have attached the problem with the solution to this thread. Basically, the problem asks to construct the circuit model for a generic device by using the data of terminal current and voltage measurements. From the table that lists the values of voltage and current, we can conclude that the device contains the resistor (rise over run) and the current source (there is some current when no voltage is applied to the device).

Homework Equations


Ohms and kirchoffs.

The Attempt at a Solution


I understand how they got 20 amp source and 10 kilo ohm resistor. My biggest question is how can I know in these type of problems, when the source is in parallel or in series with the resistor. What information did the solution manual use when it determined that resistor is in parallel. The manual, the Chegg, the textbook, and youtube with google don't seem to have answers.
 
Attachments
  • Text problem 2.30 about a table of terminal current and voltage values for a practical current source, asking to plot i_s versus v_s, build a circuit model, and predict currents and voltages.
    30.1.PNG
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  • Table of terminal measurements for Figure P2.30 listing i_s (mA) against v_s (V): 20.0/0, 17.5/25, 15.0/50, 12.5/75, 9.0/100, 4.0/125, 0.0/140, beside a schematic of a device box with a current source arrow and terminal voltage v_s.
    30.2.PNG
    6.4 KB · Views: 497
  • Two circuit schematics: a 20 mA current source in parallel with a 10 kΩ resistor between terminals, and a 20 mA source with 10 kΩ and 2.5 kΩ branches, with worked equations above.
    30.3.PNG
    15.2 KB · Views: 556
Hint: If the solution was a current source value X amps in series with a resistor what would the current be at various voltages?