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The y form of iron is known as: a) ferrite b) cementite c) perlite d) austenite

The higher the astm grain size number, the finer the gran is. a)-true b)-false

What is the chief metrological difference between measuring with a microscope and with an electronic comparator? a. the microscope is limited to small workpieces.a. the microscope is limited to small workpieces. c. the comparator can only examine one point on the workpiece. d. the microscope carries its own standard.