What should the sample size weigh?

The correct answer is based on the standard practices and guidelines established for asphalt sampling during quality control processes. A sample size of 35 lbs is typically recommended for ensuring the integrity and representativeness of the asphalt mixture being tested. This weight is sufficient to allow for various tests to be performed on the sample without compromising the accuracy of the results.

Having a sample of this size provides enough material to conduct necessary laboratory tests such as gradation analysis, density measurements, and binder content evaluations, which are crucial for assessing the quality of the asphalt. Smaller samples may not provide enough material for comprehensive testing, potentially leading to inconclusive results or limitations in evaluating the asphalt's characteristics.

In terms of the other options, while 25 lbs, 30 lbs, and 40 lbs might seem reasonable, they do not align with the established guidelines that call for a 35 lb sample size. A smaller sample could impede the testing process, while a larger one may not be practical or necessary. Thus, adhering to the 35 lbs standard is essential for maintaining quality assurance in asphalt plant practices.