I think it is either 9 from the left or 7 from the right. Who would know that the edges on 40% halves could vary so much. I've found 40% halves that you would think were 90% because the edges were so bright and showed no trace of copper.
Conversely I have seen them with the copper nice and bright and almost appearing as a copper nickel coin.
4th from the left is a modern issue, probably 1990's. 7 from the right is my guess. Secondary guess would be 2nd from the right, and tertiary would be 4th from the right.
By sound as I emptied the roll into my hand. Couldn't believe that there was silver in there as I scanned the edges looking for it, but date checking never fails!