Answer Key: Move until Dark_Unit Level

Answer Key: Unit Quiz


  1. A threshold is a cut-off value that divides a range of numbers into two groups: those above the threshold and those below.

  2. Some thresholds (like those for a light sensor) need to be calculated since they cannot be measured directly.  (i.e. if bright is 75 and dark is 25, the threshold, 50,  cannot be measured directly in View Mode, it must be calculated from the two values which can be measured).

  3. Since the threshold is 17 ((26+8)/2 = 17), the current reading of 16 is below the threshold and will be interpreted as dark.

  4. Since the Wait-for-Light Block is waiting for bright (>50), then the floor must be dark.  Since the line is 10 above the threshold, then the dark floor must be 10 below the threshold, or 40. (Alternatively, 50 x 2 = 100; 100 – 60 = 40, so the threshold must be 40).

        5.  Raise the volume to 100% and check the Wait-For-Completion box