Whats the difference between sufficient assumption and necessary assumption questions? I am struggling?

i thought we werent supposed to assume?

what does kicking up into the domain mean??? someone help

On the old site it lost all of my data and on the new site I can not log into my account! this sucks

I am getting all these questions wrong in this module. Help!

I can not understand this at all. This is a very difficult read. How can I understand this?