Answer:
T A C A G A T
Step-by-step explanation:
A becomes T, and T becomes A
C becomes G, and G becomes C on the complementary strand.
If I remember correctly, you reverse the order as well
So we have A T C T G T A
Pairing it up gives us T A G A C A T
but we have to reverse that order, giving us:
T A C A G A T