There is no particular prize for any type of contest. But the contribution you made in the resourse, business directory, classifieds and jobs awards you some cash prize as per your quality of post. So keep posting good and self made content to the site and win cash prizes.
Google Adsense account will be approved only incase of minimum 180 days from joining RS, but this can be reduced depending on your contribution to website.
Note: Google will never approve adsense if contents are copied or grammatically incorrect.
Thanks and Regards,