. A soap making process involves an addition of a small amount of sodium chloride whose concentration "x" (in grams) in the process can be modelled by the following differential equation dx = 37.5 - 3.5 x dt Initially, the concentration of sodium chloride is 50 g/L. Analyze the problem and use Euler's method (with step size h=1.5 min) to find the concentration after 3 minutes