In pea plants, purple flower color, c, is dominant to white flower color,
c. the table shows the frequencies of the dominant and recessive alleles in three generations of peas in a garden.

The law of segregation is the Mendel’s laws or principles explain that traits are passed from parents to offspring individually instead of as pairs, groups or sets.This is a law or principle which states that during the formation of gametes, two copies of each heredity factors separate out so that the new offspring can get one factor of both the parents. This law was the first law in this direction. 

The answer to this will be from your lab notes/procedure. it would be best to ask another student who participated in the lab as we do not know what was done, what enzyme or if the temperature is celsius or fahrenheit. if i were to guess though i'd say the rate stopped due to enzyme denturing at high temperature