Answer:
a
a process that selects variations to help with survi al and that spreads the variation to more offspring
Explanation:
the weak don't survive the strong thrive
Tracers are defined as elements
that can be monitored through biochemical reactions. This characteristic of tracers makes
them useful for the exploration of the mechanism of chemical reactions by
tracing the path that the they follow from reactants to products. A good
number of complex biochemical reactions (e.g. photosynthesis) have been studied
using tracers.
Answer:
Explanation:
The global average atmospheric carbon dioxide in 2019 was 409.8 parts per million (ppm for short), with a range of uncertainty of plus or minus 0.1 ppm. Carbon dioxide levels today are higher than at any point in at least the past 800,000 years.
