Q: macbook pro running slow on yosemite 10.10.2 ; also failing to recognise the wifi

Howdy niladrisg,

If you are having an issue with your Mac running more slowly than expected, I would suggest that you troubleshoot using the steps in this article - 

OS X Yosemite: If your Mac runs slowly

For an issue with being unable to recognize a Wi-Fi network, use the steps in this article -

About Wireless Diagnostics - Apple Support

Thanks for using Apple Support Communities.

Best,

Brett L