Answer:
40%
Step-by-step explanation:
In order to make this calculation it is necessary to take into account the concept of base complementarity where it is known that the 2 strands of DNA bind together by base complementarity in which adenine binds to thymine and guanine to cytosine, this reason if they tell us that 10% is adenine the other 10% is thymine, so the rest will be guanine and cytosine (80%), so the percentage of guanine will be 40%.