Are study.com psychology courses easy and very doable or hard?

[whiverem]

And how long might it take to finish one?

I'm only interested in ones that transfer to and apply to the University of Maryland Global Campus (UMGC) bachelor's degree psychology major. It seems like it would be these courses at study.com:

• Psychology 104: Social Psychology
  
• Psychology 105: Research Methods in Psychology
  
• Psychology 311: Physiological Psychology
  
• Psychology 302: Cognitive Psychology
  
• Psychology 306: Advanced Abnormal Psychology
  

Are these easy?

Are there pre-requisites for these at study.com? Can you do them in any order? I'd really appreciate it if I can find this out.

If I can do at least 3 of these, like 104, 302, and 306 I can graduate a lot faster and in no time, and at a much lower price tag.

Do you have to write anything, like an essay, or are you just taking quizes and tests to pass? Can you take quizes or tests unlimited number of times, or is there a limit, without paying more? Lots of thank you.