Shashi,
I beleive that from what I am seeing that you would have to create the datum pints in a sketch at each end of the slots that you have created. Then accept the sketch. Using these points you can place axis lines thru two points for each of the slots. This will be very time consuming!
Just wondering what does the cross section of the slots that you created. If there is a rounded bottom on the slots then you can forget the sketch and just place the axis on the center of that rounded bottom. If it has a flat bottom then you wiill need to use the sketch.
Just remember to use the "DATUM POINT" not the "SKETCHING POINT". Sketching points will not show up after the sketch is complete.
Good luck.
Kevin