The correct answers are as follows:

This is a condition. Again the food being organic would be fundamental to the contract as the health of the llamas depend on it.
This is arbitration as it involves a panel.
This is an innominate term as it won't be mentioned in the contract. It won't be until a breach occurs when it is decided whether the issue of subcontracting is a condition or a warranty, and which one it will be, will likely depend on the situation. For example if they subcontract out to a non-organic llama food provider, that would probably be a Condition. If they get help fulfilling an order and the subcontractor is also organic, that's probably a warranty.

Documentary collection is used in international transactions where there is trust. This is explained on p. 35 It's basically when supplier and buyer delegate collection of payments to their respective banks. They need to trust that each other will actually pay - otherwise they wouldn't delegate this. A Letter of Credit is a documentary credit confirmed by a bank, usually for export. A Bill of Ex-change is a promise to pay at a later date, usually supported by a bank. Stage payments are used in big purchases, such as construction projects where payment is given to the contractor when certain milestones are hit.

The correct answer is 1. The statement is True so the answer needs to start with 'yes'. Therefore options 3 and 4 should be discounted. Option 2 is incorrect a warranty does NOT affect the prime benefit of the contract. See p. 126 for more details on Contractual Warranties and Conditions

The correct answers are as follows:

This is a contract variation as they are changing the number of staff and their hours

The correct answers are as follows:

This is payment terms. The scenario mentions processing invoices, which is to do with paying the supplier