What does let us know mean, what does fair enough mean?

Question

What does let us know mean, what does fair enough mean?

Answer 1

Let us know mean keep us posted.

Fair enough means it's okay.

Answer 2

let us know means please inform me

fair enough is like saying oh alright then.  that explains it

Answer 3

Let me know too but fair enough if you don't !

Answer 4

let us kno= when u are certain about something then let that person kno too

fair enough= thats fair if  YOU agree

Answer 5

Let us know when you think this is a fair enough question to answer!!!

Answer 6

LET US KNOW - We care about this situation but at the same time we don't want to be of any bother so please let us know how the situation is plays out.

FAIR ENOUGH - That isn't exactly how I see it however since you have told me how and why you see it that way, I cant understand a little better.  You still didn't convince me to change my way of thinking however.

This is my take on those two generic comments.