Which of the following boring tool is used for deep boring?

____________ are the pieces of wrought iron and are bent at ends to connect other members.

The content of oxygen is normally ____% in air.

The structural elements made of ______ gets Ignite and get rapidly destroyed in case of fire.

___________ are the rings of metal which can be used for fasten two members abutting each other.

A _______ joint is formed by making projections and corresponding depression on the other piece.

______________ are the pieces of wrought iron or steel and these are driven into the member to be connected using hammer…

The figure below represents ___