Hi getnet and welcome to INForum!

I haven't seen any significant .net.in sales. It's not really a popular extension in the domain aftermarket.

Those are really strong keywords, and they are probably worth something to an SEO type - around high $xx to $1xx.

Other than selling them on, to make some money from them you'd need to develop them. I doubt that they would make much from parking but it doesn't hurt to test that out before you do anything else.