The answers are the ones I have checked. I just don't understand at all why they are correct. I also do not understand why the rest are wrong although I do have some suspicions. I do know for a fact that (AB)^(-1) = B^(-1) A^(-1) so C is automatically wrong but for B, is it wrong because of the order? Could someone please explain or elaborate if I'm correct? Also, I have no idea why D or E are wrong.
Any input would be greatly appreciated!
Thanks in advance!