50 POINTS 4. If a DNA molecule has 40% Cytosine, what percent of it would be Adenine?

The possibility of Adenine=40% and Thymine=60% is only in single stranded DNA molecule. In the question, the DNA sample referred is a single stranded DNA. If guanine=10% as guanine will always pair with cytosine, i.e. cytosine is also 10% then adenine and thymine accounts 80% as adenine will always pair with thymine.

Explanation:

20%

Explanation: Cytosine has always the same amount as Thymine. If there is 30% of Adenine, then there would be 30% cytosine, leaving 40% left over.

Adenine and guanine are always the same amount, so you get 40% and divide it by 2, so it is 20% of adenine.

the answer to your question is b