All you have to do is keep track of what letter matches which letter in each column. For example
(DNA strand B) A= (DNA strand A) T
You have the matching letters for each. Do you understand? If not I can help clarify. :3
Answer - The chromosomes has to be crucially duplicated and it happens actively during the resting phase or interphase.
Reasoning - During the resting phase or interphase you call it, Is important to have the same exact DNA or Chromosomes to be duplicated. If the chromosomes did not duplicate during the interphase then the split of the cell would be unbalance and uneven and likely to cause defects.
Answer:
Genotype of long winged fly is Ll
Genotype of short winged fly is ll
Explanation:
Given
Allele for long wing trait is "L"
Allele for short wing trait is "l"
When a long winged fly is crossed with a short winged fly, half of the offspring have long wings and other half have short wings as the ratio is 
Let us say that the genotype of long winged fly is Ll
and the genotype of short winged fly is ll
The cross between the two will produce following offspring
Ll * ll
Ll, Ll, ll, ll
Out of four off spring two have long wings (Ll)
and the other two have short wings (ll)
Thus the ration of long to short wing offspring is
i.e 
Answer:
the answer is D i believe.
Explanation:
I believe so, dont take my word 100% on it though.