1: 4-down Arias hit high note in some of the lungs (3,3)
3: Al's gamble on outcome of sports (4,5)
4: Demand payment? Just so! (5)
5: There's uranium in many a flower (5)
8: Introduction to book by mere poet (5)
9: Flower inducing forgetfulness in vaudeville theater (5)
12: Without it, set call for recompense (3)
13: Managed in lower Antwerp (3)