135. Solving a chemistry problem

10 l of air from the production room containing hydrogen chloride was passed through 20.0 ml of water in an absorption vessel, after which 5.00 ml of the resulting solution was taken into a test tube for nephelometry using the scale method. At the same time, a series of standard solutions was prepared by adding V ml of KCl solution (T=0.01023 mg/l) to the same test tubes. The same volume of HNO3, AgNO3 was added to all test tubes, the volume was adjusted to 10.0 ml, mixed, and after 10 min the turbidity of the test and reference solutions was compared.
Determine the concentration of HCl (mg/m3), if the equality of turbidity was observed at the following values ​​of V:
Option 1
V, ml 0.5