9. Equations for which kinds of reactions are best balanced by the half-reaction method?
reactions that take place in acidic solutions
reactions that depend on double-replacement
reactions that occur spontaneously
reactions that involve decomposition

hey your not cool]      

in scientific notation, the value of the  speed of light in a vacuum

  will be written as 2.995 * 10^8. when this value is represented in the form of

  a * 10^b, then, a = 2.995 and b = 8.

the value of the speed of light in a vacuum given above can also be rounded up to approximately 300000000. in this case, the scientific notation will be written as 3 *10^8.

oxygen, selenium, tellurium, and polonium.

they're all from the same group as sulfur (group 16).