It's impossible to answer for two reasons. 1) we don't know what % of your visitors are going to click the adverts and 2) we dont know how much each click will pay.
You should be able to work it out by looking at your current earnings, then do a little maths.
Yeah, if you know the eCPM, you can calculate it easily.
Otherwise, its hard, depending on the nature of your site, the niche and geographical area of your vistors, it can vary a lot. I mean A LOT, its hard to generalise. Some clicks can pay you on few $ and some would be as less as 5 cents.
