More bushels or potato's will be produced if the soil is fertilized more what is the independent variable

Which line in the graph above best illustrates an effect of the carbon dioxide level in the blood on breathing rate before, during and after a period of exercise? 1.b,2.c,3.a,4.d

Genes that come together with different alleles are heterozygous. homozygous. genotype. segregated.

We all have different forms of genes from our parent(s).what are these different forms called? a.alleles b.characters c.dna d.resources