Answer:
AGCGATAGCAA
Step-by-step explanation:
Adenine → Thymine (A → T)
Thymine → Adenine (T → A)
Cytosine → Guanine (C → G)
Guanine → Cytosine (G → C)
With that being said, you just switch the letters up to get the correct answer. Does this make sense? You're just switching the letters.