AMAZON CAL

Hi experts,

     Just want to ask the per HOUR of AMAZON when running the instance. Is it when I run the instance it will charge me $0.56 even though I didn't consume 1 hr. For example: I've run the instance for 15 mins then disconnect and run the instance again for 10 mins, thus it charge me for $0.56? Or should I consume first the 1 hr to charge me the $0.56?

Regards,