Answer: Manholes are usually round, primarily because roundness is the best shape to resist the compression of the earth; covers are round because they are easier to manufacture than square or rectangular shapes, they are easier to move by rolling, and they can't fall into the opening.
Explanation:
The correct answer is the 3rd option Ductility is a property of a metal. It is the ability of a material to deform under tensile stress.It is characterized by the ability to be stretched into wire-like form which is an ability of metals.
Answer:
iron (III) oxide is a gas