97 Pathfinder wont start

My 97 Pathfinder (Auto Transmission) wont start. It will barely turn over after sitting for a while and then eventually just a fast "click, click, click". The battery is providing about 9.4 volts. Is this enough to charge the starter? All internal lights and power are functioning and a jump start wouldnt work. The battery's positive terminal had alot of corrossion, but cleaning it didnt help either.

Im sure its either the battery, starter or alternator, but Im not sure how to pin point which is defective.

Any suggestions would be greatly appreciated!