Answer:
A and T occur in similar proportions.
G and C occur in similar proportions.
Explanation:
There are four nitrogenous bases that form integral part of DNA, these are Adenine (A), Guanine (G), Thymine (T) and Cytosine (C). Due to specific base pairing between these bases, (Adenine is always linked to Thymine through two double bonds and Cytosine is always linked to Guanine through three double bonds), it is estimated that A and T occur in similar proportions. while G and C occur in similar proportions. This was proposed by Chargiff for the first time and now it is considered to be as Chargiff rule. You can see chart in attached image to know that how equal the ratios are found experimentally in different living organisms.
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