Question

An engineer is designing a play set for an elementary school. The drawing above shows the detailed view for the pre-drilled holes for the mechanical fasteners used to assemble the play set. Which note below could annotate the hole(s)?

Answer 1

This is a case of counter bore holes. The correct answer is C.

Where:
2 ---- Indicates two holes.
∅1.25 THRU ---- Shows that the holes have a diameter of 1.25 through the material.
Then, there is a counterbore of diameter 2.25 and a depth of 1.00.