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Sure. It takes SBD, of which you have 4.6, so thats the limit to which you can spend. When you click the Promote button, you'll see your balance too, and if you use balance less than that, there shouldn't be an issue. Also, you might want to see how much others are spending on promotion and what placement they're getting. Here's a post I did a while ago: https://steemit.com/steemit/@graphicalx/how-to-see-how-much-someone-paid-to-promote-a-post

Let me know if this helps or if you have any questions!

Yes, thanks, now it worked. Just needed to turn my phone sideways to see the "amount" field properly