A contract in writing was entered into between buyer A and seller B for the sale of 200,000 tons of quartz sand to be delivered in four loads of 50,000 tons per week as required, with each delivery to be paid for separately. The written agreement provided that the sand was to be of a specified silicon dioxide and with particles of a certain size (Quality). B was responsible for ensuring the sand was of the specified Quality and it was made clear to B that A would test the Quality itself, but it would not have results of those tests until after the sand was used. A informed B that if the sand was not of the specified Quality, the glass made from the sand would not meet the Australian standard and would have to be destroyed, causing damages to A. The first and second loads were delivered and used, and two further loads were delivered but not used, although the fourth load was of only 40 tons. When A got the results of its sample for the first and second loads, it realised that it was not to the specified Quality. A informed B that it would not accept the third and fourth loads, even though they were of the specified Quality, and that it was rescinding the contract. Can A rescind the contract having regard to the SOGA? Your answer should have regard to relevant case law. Would your answer change if only the first delivery was defective, and that defect was not sufficient to have any effect on the quality of the glass?