Ok, so
Let me draw the figure here below:
We have to find the measure of arc AC.
For this, if we apply the equidistant chord theorem, we got that mAB = mCD = 104°.
But, we need to know the measure of BC or AD.
Apparently, I think the question is missing some information. Think about it, we could decrease or increase the arc BC without changing anything that its given.
It could be this:
Or, it also could be this:
And both have the same measures.
