67) While power feed is engaged when turning taper by using taper turning attachment, it is noticed that for short distance parallel turning takes place due to certain defect. Which one of the following is the cause for this defect ?

68) For cutting acme threads, the threading tool should be ground to an included angle of

69) To cut 20 mm internal square thread with a pitch of 2.5 mm, the core diameter should be

70) Dovetail chasers are clamped in a

71) When cutting ISO metric threads of coarse pitch, the compound rest should be swiveled to