Question 494General Subjects - Assistant Engineer

The correct answer is A) 0.025 inch. The micrometer is a precision measuring instrument that uses a thimble-shaped barrel to linearly move the spindle in increments of 0.025 inch per full revolution of the barrel. This is a standard specification for the majority of micrometers used in various applications, including those referenced in the US Coast Guard Captain's License Examinations. The other options are incorrect because they do not align with the standard micrometer specifications. For example, 0.110 inch, 0.205 inch, and 0.250 inch per revolution would be outside the typical range for a standard micrometer.