S1 The variation within a batch as provided in Table A1.1 shall be determined for each property listed as the difference between the highest value and the lowest value obtained from the different portions of the same batch. S2 For this specification, the comparison will be between two samples, representing the first and last portions of the batch being tested. S3 Test results conforming to the limits of five of the six tests listed in Table Al.l shall indicate uniform concrete within the limits of this specification.