21. Solving a chemistry problem

2. To construct a calibration curve for the photometric determination of ammonia, the following results were obtained:
СNH4OH, g/l 0.96 1.28 1.44 1.76 1.92 2.08
Reading on the photocolorimeter scale, x 27.5 38.1 45.7 59.1 69.0 82.4
Plot the calibration plot on a logarithmic scale. calculate the coefficients of the equation СNH4OH=А Вlgx. Using the A and B values, calculate the CNH4OH(g/l) in the test solution if the photocolorimeter reading for this solution is 90.5.