Q:
Design and draw the circuit of a non interting Schmitt trigger. It is to operate from a dual 15 volt P.S.U and the output has 0v saturation. The hysteresis required is 0.281v at the upper and lower trip points (i.e. hysteresis = 0.562v). Calculate suitable resistor values.

and I don't understand the output has 0v saturation part in the question

 

I'm not sure what they mean. The only things that makes sense is that they are saying that the difference between the output and the supply rail is 0V when it is saturated.

 

I'm not sure what they mean. The only things that makes sense is that they are saying that the difference between the output and the supply rail is 0V when it is saturated.

I agree. It probably means that the output will swing rail-to-rail, independent of the load. This makes calculations simpler.