Have mountain lion on Mac and airplay is not working. Cant see the icon.

My mom's Macbook says its Mid 2010. Does that mean she wont get airplay? Cause we were really looking foward to airplay.

I read the troubleshooting and on itunes I noticed the airplay icon. I did all stuff I thought it would help. I even watched a video about mountain lion and all its features. I dont see the icon on menu bar, si im guessing its not for this mac model. Or maybe im doing something wrong. Network is all the same, apple Tv was purchased in May this year so it new version and airplay is on. Airplay works well with all our iphones and my ipad. I even turned off firewall on the mac. My mom has no clue how to do all this and i have a windows at my house. I know this has nothing to do with this topic, but after I upgraded her mac to mountain lion I noticed that when we open Safari or Chrome, we dont see the bar on side to scroll down or up. It goes away after a few seconds. Is that normal?

Thank you so much for my 2nd problem. I guess the airplay and Mountain Lion problem Im not the only one having. Very disappointing if you ask me. $20 and the one feature I know my mom would use doesn't work because her mac is a bit too old.