To stress relive a cold worked steel part, it is heated to a temp close to ..... A....... and grains obtained after cooling are........ B.........
A. Lower critical temp/ upper critical temp
B. Fine / coarser

The diameter of the best wire to measure the effective diameter of a metric screw threads of $$0.5$$ $$mm$$ pitch is ......... $$mm$$

The skid in a stylus type roughness measuring instrument is used to provide ............ A .............. and define ................... B .............. geometrical profile of the surface.

$$A.$$ support / datum
$$B.$$ micro / macro

A shaft of diameter $${20^{\matrix{ { + 0.05} \cr { - 0.15} \cr } }}$$ and a hole of diameter $${20^{\matrix{ { + 0.20} \cr { + 0.10} \cr } }}\,\,mm$$ when assembled would yield.