Answer:
DNA Sequencing.
Explanation:
In field of Biotechnology, we use an instrument known as "Gel Electrophoresis" in this instrument, different sized DNA Fragments are placed. After that, Electricity is applied due to which Negatively charged DNA fragments move towards positive charge through Gel Medium. Small sized DNA Fragments reach destiny before large fragments.
This is an application of Electrophoresis.
<u>Answer</u>:
The null hypothesis: the mean egg thickness is 0.2 mm 
The alternative hypothesis: the mean egg thickness is less than 0.2 mm 
In statistics, the null hypothesis states that there is no significant difference between the observed value and the mean thickness. The alternative hypothesis states is the opposite and states the scientist's "idea" behind the experiment. Here, it refers to the fact that due to DDT, the egg shell will be thinner compared to the mean value.