Why can't scientists simply use carbon-12 (12C) do determine the age of dead carbon-based life forms?

carbon-12 is not radioactive

Explanation:

The measurement of the age of dead carbon based life forms requires the use of a radioactive isotope hence it is often referred to as radiocarbon dating.

Carbon-12 and Carbon-14 occur together in living things.The half life of Carbon-14 is about 5670 years.

Hence, since Carbon-12 is not radioactive, it can not be used to measure the age of dead carbon based materials.

right

explanation:

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.