What is the representative sample quantity for cocaine in liquid form?

The correct choice for the representative sample quantity for cocaine in liquid form is based on established practices for sampling liquids in order to ensure that the sample is representative of the whole. In this context, taking 25 gallons from each tank provides a sufficient volume for analytical testing while ensuring that the sample reflects the composition of the entire tank.

Sampling in large enough volumes like 25 gallons is essential when dealing with liquid substances because it minimizes the risk of sampling error, which can occur if the amount taken is too small. A larger sample size allows for a more accurate assessment of the characteristics of the liquid, such as concentration and purity of the cocaine. This is crucial in law enforcement and legal contexts, where the results of substance analyses carry significant implications.

Smaller sample sizes, such as those mentioned in the other options—10 kilograms from containers, 30 ml from individual samples, or two kilograms from tanks—might not adequately represent the entire volume, especially if there are variations in the composition throughout the liquid. Thus, using 25 gallons strikes a balance between practicality and ensuring that the sample is indicative of the entirety of the liquid contents. This methodology aligns with best practices in sampling procedures and helps to uphold the integrity of forensic analysis.