21. Solving a chemistry problem

2. For four standard solutions containing chromium, their polarograms were taken and the following results were obtained:
Samples No. 1 2 3 4
С(Cr)*103, mol/l 0.3 0.42 0.96 1.4
h,mm 8 10 20 28


A weighed portion of the analyzed sample q g was dissolved in a mixture of acids and made up to the mark with water in a 100 ml volumetric flask. During polarography of this solution, hx, mm was measured. Build a calibration graph and perform calculations in accordance with the option:
Given Options
12
q,g
hx, mm
ω(Cr),% 1.8025
22.0
- -
14.0
0.25
Calculate: ω(Cr),% q,g
Solve both!