It represents the number of moles required of that molecule to balance the chemical equation, which means to have the reaction chemically happen and goes to completion.
For example:
CH4 + O2 --> H2O + CO2 that is not balanced
with the coefficients located
CH4 + 2O2 --> 2H2O + CO2 now with the coefficients the number of oxygen and hydrogen on each side are equal
An element cannot be broken down any further. Elements can be found on the periodic table
The half life for C14 is 5730 years.
We assume that Carbon 14/ Carbon 12 ratio was steady for living organisms over time, the problem is actually telling us that

= 0.0725 =

ˣ
Take the natural logarithm and In on both sides.
ln(0.725) = ln

ˣ
= - 0.3216 = xln (

= -0.6931x.
So x = (-.3216) / (-0.6931) = 0.464
or
t/t₁/₂ = 0.464
So t = 0.464 x t₁/₂ = 0.464 * 5730 yrs = 2660 years.
The answer is a. hemoglobin is the molecule that transports oxygen in red blood cells :))))
i hope this is helpful
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