On Saturday evening she received a call from Kevin, whose son Jeremiah is struggling in his grade eleven math course. Kevin and Phoebe agree that Phoebe will meet with Jeremiah at his house at 4:00 on Tuesdays, for a period of four weeks.

On Tuesday morning Kevin called Phoebe and told her that he had decided to hire a different tutor. Phoebe consoles herself that she will not have to spend $5 on gas to drive to and from Kevin's house every week, but she is still upset by the cancellation. Later that day she received a voicemail from Leilani, a high school student, who wanted to discuss hiring Phoebe for six weeks' of tutoring. Phoebe sues Kevin to recover damages for breach of contract. Which of the following represents the most accurate analysis of her entitlement to damages:

a) Phoebe is entitled to recover $160 from Kevin.

b) Phoebe is entitled to recover $140 from Kevin.

c) Phoebe is entitled to recover $160 from Kevin unless Leilani hires her for six weeks.

d) Phoebe is entitled to recover $140 from Kevin unless Leilani hires her for six weeks.