The distillation column shown in the drawing is used to distill a binary mixture. symbols x, y, and z denote mole frac- tions of the more volatile component, while b, d, r, and f represent molar flow rates. it is desired to control distillate composition y despite disturbances in feed flow rate f. all flow rates can be measured and manipulated with the excep- tion of f, which can only be measured. a composition ana- lyzer provides measurements of y.

Alice did an experiment to find the relationship between the angle at which a ray of light strikes a mirror and the angle at which the mirror reflects the light. she placed a ray box in front of a mirror. she changed the angle at which the light from the ray box struck the mirror and noted the corresponding angle at which the mirror reflected the light. which of the following is the dependent variable in this experiment? the mirror used to reflect the light the ray box used as the source of light angle at which the light from the ray box strikes the mirror angle at which the mirror reflects the light from the ray box