The Canberra Cat Caf (CCC) is in the Australian Capital Territory. Visitors pay an entry fee to interact with cats on the premises. Claire is the manager. Maple supplies cat food. On Monday, Claire orders 20kg of cat food to be delivered on Friday. Maple replies, "I can do that for $100". Claire says "Okay, great, I'll transfer the money now". On Tuesday Maple tells Claire that she only has 15kg of cat food in stock. Claire says "that is disappointing, can you deliver it on Thursday instead, and refund $25?". Maple agrees, and delivers 15kg on Thursday and refunds $25. On Friday Claire demands that Maple deliver 5kg of cat food for free. Advise Maple.