If you have not already done so, download Avogadro for free and watch the tutorials if necessary.
Open an Avogadro page, build the nitric acid molecule and optimize its geometry (sequence Extensions → Optimize geometry), then study its properties. Why does one of the two oxygen atoms – to which hydrogen is not attached – has a single bond, while the other oxygen binds nitrogen with a double bond? What else do you notice about bonds?
Indicate which type of hybridization and which molecular geometry the nitric acid molecule has.