this is the question. word limit 300. i need a framework on hoe to solve the question. this is the full question

On 1 March Ausbank e mailed Ultracorp: "Will sell you Ausbank's Gulfstream IV jet for $NZ40 million. Payment and delivery on 1/5/2020. Engine and avionics specifications, details of seating configuration, engine hours and maintenance details are as follows... [detailed technical specifications followed.] You may well reject this first-off but upon further consideration we believe you will accept. Accordingly offer is open for 1 week from 1/3/2020". Ultracorp immediately emailed back: "Offer is ridiculous and rejected accordingly". On 3 March Ultracorp e mailed Ausbank: "Changed mind, we accept offer. Will pay $NZ30 million on delivery and $NZ10 million interest free on 1/12/2020". On 4th March, Ausbank sold the jet to Eric, an internet entrepreneur. This sale was reported on the Aviation News website. Chuck, the CEO of Ultracorp follows the Aviation News blog but didn't notice the report. On 7th March, Ultracorp, having heard nothing from Ausbank, posted the following letter: "Funds have come available earlier than expected and we can now let you have $NZ40 million immediately. Accordingly, we accept your original offer. Please advise soonest how you wish to settle". This letter was received by Ausbank on 8th March. Analyse each stage of this transaction and advise whether or not Ultracorp have a binding contract with Ausbank for the sale and purchase of the aircraft. (10 marks)