How to determine ROI for Social Media? Please Help!

Hi,

Now a days Social media is booming like anything. I have few doubts about social media. Please Question are as follows


1. Is Social media is really a good online marketing channel to drive traffic and quality leads?

2. How a business can take advantage from social media?


3. What are the ways and means to followed to drive traffic from social media?


4. How long it will take to drive a good traffic & return from social media?


5. How to determine ROI for social media?

Please Help!

Thanks in advance