After performing a 'bump test' to a mixing process with unit step change in the dilution flow (say, 1 L/sec), we have got concentration (or consistency) change as a function of time, sec (a file with data points is provided).

1. If the response is assumed to be a first order system with time delay, determine the constants of the process transfer function. Compare the fitted process with the original experimental data (two curves on one figure)

2. Determine the response of the mixing process to a sinusoidal change in dilution flow with amplitude of 0.5 L/sec and time period equals to 2 time constants.