2.fertilizers which are used to grow crops are_considered pollutants.
a.never
b.sometimes
c.always

3.which of the fallowing is not a direct cause of breathing problems?
a.sulfur dioxide
b.nitrogen oxide
c.ozone
d.lead
e.particulates
ab.all of the above
ac.none of the above

4.why are most of our current energy sources not concidered as fuels for the future?
a.they dont produce enough energy to meet our needs
b.theres not enough supply
c.they cause pollution and health concerns
d.all of the above
e.none of the above

5.which does not represent kinetic energy?
a.water used to turn turbines
b.wind used to generate energy
c.steam used to run an engine
d.wood which will be used later to hear a house
e.all of the above
ab.none of the above