Probability questions explained

Hello pals here are few probability questions which are explained ( the tougher ones only) 

Here is the link: Probability questions-1
Disclaimer: Everyone, i don't own these questions, neither do i frame them!  I found them at test magic forums and tried to explain you with tactics i know! I hope you'd not mind it if you have already crossed these questions, it's just to help someone who needs it! thanks for reading!