Why is it important for steel to go through a fluid phase as it is being produced?

Which of the following statements is not true? • a. covalent compounds have low melting and boiling points. • ob. covalent bonds between atoms of a compound are relatively weak compared to bonds between molecules. • c. covalent bonds occur between nonmetals. • d. covalent compounds are often gases or liquids.

Iknow the answer is a but i don't know why

Draw the skeletal structures of two different molecules that are each made of 5 carbon atoms and 12 hydrogen atoms.