jim's contract with frank obligated jim to pay frank $10,000. frank properly assigns the contract to abel. at that time, abel notifies jim about the assignment. jim, however, forgets and pays the $10,000 to frank. by this time, abel is screaming for his money. however, by then, frank goes into bankruptcy. in this case: a. abel is out of luck because his notification was oral rather than written. b. jim is liable to abel not for the $10,000, but for his breach of the implied warranty that the assignor is solvent. c. jim is liable to abel for $10,000. d. abel is out of luck because jim performed his obligation by paying frank.