Carbon nanotubes are made of the same material as the graphite found in pencils, a material soft enough to leave an image on
paper. Although carbon nanotubes are much smaller than a human hair, they are stronger than steel. What factor accounts for this
strength?
They are extremely elastic.
They are a mass of ionic carbon to carbon bonds.
They are created using high pressure then super-heated.
They are composed of unbroken chains of covalent carbon to carbon
bonds.

Which sentences describe point source pollution? in this type of pollution, the source of the pollution is single and easily identifiable. when runoff water from the melting of snow mixes with debris, it creates pollution. the runoff water, mixed with pollutants, reaches large areas with disastrous effects. alternatively, when a wastewater treatment plant releases harmful chemicals into a stream, the chemicals pollute the stream water because they are not treated for safety.