Solving a chemistry problem

3(1). A sample of an organic compound weighing m g was subjected to pyrolysis under conditions where the sulfur present in the substance turns into hydrogen sulfide. Gaseous decomposition products after chromatographic separation of cyanogen were passed into a conductometric cell containing a solution of mercuric nitrate. As a result, the solution resistance in the cell increased by ΔRx. Standard substances with a known sulfur content in them were subjected to the same transformations and the corresponding ΔR values were measured. The measurement results are shown below.
Sulfur content in the sample, mg 0.240 0.260 0.280 0.300
ΔR, cm 450 480 510 540
Construct a calibration graph and calculate the mass fraction (%) of sulfur in an organic compound using the following data:
OPTION 1
m, mg 1.315
ΔRx, cm 430