(a) A unilateral offer cannot be withdrawn after the offeree has begun performance of the stipulated act.' Discuss. (b) Count Cristo is an art collector. His favourite painting, Hams Peter Piper', is stolen. Count Cristo places an advertisement in the Times newspaper offering a reward of 50,000 to anyone who is able to locate the painting. Advise Count Cristo in each of the following alternative circumstances: i) Sherlock, a private investigator, is employed by Count Cristos insurance company to recover the picture. Sherlock locates the picture and claims the reward. ii) Donna, who does not read newspapers, finds the painting lying in a public park and sees Count Cristo's name and address behind it. She returns the picture to Count Cristo who thanks her profusely. She later finds out about the reward and is insisting that Count Cristo give her the reward. iii) Lestrade, a police detective working on the theft, locates the picture and claims the reward