What is meant by the term Reference Front?

Explanation:

The RF value is defined as the ratio of the eistance moved by the solute(i.e the day or pigment under test)and the distance moved by the solvent (known as solvent front)along the paper,where both distance are measured from the common origin or application baseline,that is the point where the sample is

in the year 2850, humans successfully colonized mars. the martian modules that were constructed could hold only a small population of people. it is now a century later, and the population on mars has grown to 600 people. of the current mars population, 45 people express the recessive phenotype for phenylketon- uria (pku) syndrome (pp genotype).

explanation:

a=c and then d= c because of the band so you get ac/dc and you add them together you get sound waves