No genuine zeros "Absolute zero" (absolute zero), but assuming zero. The test center does not mean that students do not know yet. Zero degrees Celsius, does not mean that no heat at all.
No real Center or "complete zero" (Absolute Zero), but it is assumed, for example, have students work does not mean there are no knowledge at all. Zero degrees Celsius does not mean that there is no heat at all.
There is no zero genuine, or "center" (Absolute Zero) but is a center such as student testing center assumes no means that there is no knowledge center. Degrees Celsius does not mean that there is no heat at all.