The standard for a HPLC investigation was prepared as follows: A weight of 192.6 mg of pure reference material (Wstd) was mixed with 2.0 mL ("V is std") of an internal standard stock solution and the volume was then made up to 25 mL ("V1"). This intermediate standard solution was subjected to two more dilution steps: 5mL ("V2") of the first intermediate standard solution were diluted to 25 mL ("V3") and then 4 mL ("V4") of the latter solution were diluted to 25 mL ("V5"), to yield the standard solution that was injected to HPLC. The first part of the investigation required an External Standard analysis. Identify which standard concentration is employed in the External Standard analysis and report its value. Enter your answer in regular (decimal, not scientific) format, with 4 (four) significant figures and no units.