Answer:
40% is Adenine.
Step-by-step explanation:
In DNA, Guanine pairs with Cytosine and Adenine pairs with Thymine.
If a strand of DNA contains 10% Guanine, that means that it also contains 10% Cytosine.
10% G + 10% C = 20%
100% - 20% = 80% (Adenine and Thymine)
80% ÷ 2 = 40%
The strand of DNA contains 10% Guanine, 10% Cytosine, 40% Adenine, and 40% Thymine.