attach I need help number 12 only

Question

anonymous · Answer

attachment

anonymous · Answer

I did graph number12 but I don't know how to answer

radar · Answer

Your graph appears to be correct, however, only the portion appearing in quadrant I and II are pertinent.  If R1 becomes 0 there will be 1.2 amps of current.  And resistors do not become negative values, the lowest resistance can become is zero (a short)
I would say you have accomplished number 9.  Lets look at 10.

radar · Answer

10 doesn't seem to be a problem.  11 plug the 140 into the function and you will come up with an I value of .5 A   (500 ma)

As I said only the positive values of R1 are realistic.   so that should take care of 12.
Good luck with this.  An interesting course you are taking.

radar · Answer

Remember $$R _{1}\ge 0$$

anonymous · Answer

thank radar.Please! come back help again