Answer: superhelix
Explanation: its definately the correct answer
A goes with T, and G goes with C. If there is 30% guanine that means there is 30% C. Which leaves 40% of A and T. Therefore the answer is 20% Adenine.
The variable that researchers manipulate is the independent variable.
The reason for this is because in experiments different manipulations are often introduced. The sole purpose of these manipulations is to see whether they will affect our independent variable and if they will change its value.