Determining the nucleotide sequence for the RNA is pretty simple. Remember that C and G pair together in both DNA and RNA. So when you write out the RNA sequence C's will become G's and vise versa. In DNA, A and T make a pair, however in RNA A and U form a pair. Therefore, any where there is a A in the DNA strand, the RNA will have a U.
DNA template : CGGATCAT
RNA : GCCUAGUA
If you were looking for the other half of the DNA strand, you would just replace any U's with T's.