Why is it difficult to assign a numerical age to a sedimentary rock?

Explanation:

The order of occurrence of the sedimentary layer is related to a local igneous body that has been radiometrically dated, thus yielding an age range for the sedimentary layer.

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.

answer: they produce more slow than unicellular organisms.