In assessing whether fluoridated water can cause
cancer, what do the national research council,
national health service, and centers for disease
control and prevention all agree on?
osteosarcoma is so rare that there is little
need to study the risk of fluoride.
fluoride should not be added to water
according to research from dentists.
there is a need for further research.
done

There is no need for further research.

Next one is: It is difficult to tell if fluoride causes this cancer

Explanation:

28. evolution

29. environment, survive, offspring  

explanation:

explanation:

earth's surface is mainly heated by the absorption of infrared radiation from the sun.

evaporation occurs because molecules in liquid water are warmed ( usually by the sun) and vibrate quicker, becoming less dense and rise.

condensation occurs because molecules in water vapor are cooled and therefore vibrate more slowly thus becoming more dense and eventually fall to earth.

lines of equal barometric pressure on a weather map are called: isobars : lines of equal temp on a weather map are called: isotherms.​