Jon Was Developing a Computer Program for Use by Owners

Jon was developing a computer program for use by owners of track clubs, which would aid them in keeping records of the members, their runs, times, injuries, etc. Eager to finish the program, Jon, in Edmonton, called his friend Sam, in Calgary, and offered him $4000 to help: five hours a working day, five days week, for five weeks. Sam said that he would have to think about it. Jon told Sam that he was eager to get going, but that he would hold the offer open until Friday, February 6, 2011, at noon. Which of the following is true? (Read each separately.)

A) If Sam accepts by phone within the time specified in the offer, the place of contract would be Calgary.
B) If Jon goes ahead and hires Betsy from Edmonton at noon on February 3, it would be too late for Sam to accept.
C) If Jon revokes his offer before Friday noon, Sam could sue him for breach of contract because he promised to hold it open.
D) If Sam wants to ensure the promise to keep the offer open until noon, February 6, he should give Jon some consideration (that is, allow him to purchase an option) .
E) If the court held that acceptance by mail was reasonable in the circumstances, if Sam accepts by mail the place of contract is Edmonton.