How can we trace enhanced co2 atmospheric levels back to human activity? site; ?

There is no carbon dioxide balance in biomass output or input. There is no dynamic equilibrium since carbon dioxide is being released at various rates. Geologically carbon dioxide concentration was very high for a long time and high enough to preclude evolving oxygen breathes until when carbon dioxide was locked up in plant life and oxygen levels raised by cyanobacteria and algae.

Oceans release carbon dioxide or it absorbs less carbon dioxide which causes a rise in temperature which feeds back. More heat is lost through evaporation which is lost to upper atmosphere then land biomass starts to pick up.

the answer for this question would be d. glaciers

an organism's phenotype is the  form of a trait  that it  displays. for  flowercolor, a pea  plant  can  display  a phenotype of purple or white flowers. an organism's  genotype  is the alleles of a gene it contains. based on his data, mendel concluded that a phenotype can be  determined  by more than one  genotype.