Questions

Cast iron is a group of iron-carbon alloys with a carbon content greater than 2% and is a brittle material.

Its usefulness derives from its relatively low melting temperature.

Plants grow in size both in height and in girth. Enlargement of cells already present cannnot contribute much to the growth. Only addition of more and more cells could increase the size of the plant considerably.

Phosphorescence is a phenomenon associated with an algal division called euglenophytes. 

Phosphorescence is a phenomenon when an object is capable of releasing photons of light at a longer wavelength in response to absorbing light of a shorter wavelength. The object releasing the light only releases the light after some time has passed since it absorbed the light of a short wavelength.

Euglenophytes are single-celled plant-like protists that have no cell wall.

It is using a router to answer ARP requests. This will be done when the originating host believes that a destination is local, when in fact is lies beyond router.

Labyrinth which is part of the ear is the main organ of balance in the human body.