* The institution: Different colleges and universities have different course structures and credit hour systems. Some might offer a single 3-credit accounting course, while others might offer multiple 3-credit courses (or even 4-credit courses) per semester.
* The student's level: Undergraduate students typically take fewer credits per semester than graduate students. A graduate student might be able to take more accounting courses (and thus earn more credits) than an undergraduate.
* The student's program: An accounting major will likely take more accounting credits per semester than a student who is only taking a single accounting course as an elective.
To find out how many accounting credits *you* can earn in a semester, you need to check your university's course catalog or speak with an academic advisor.