i wonder what the most efficient ad is... i tried "promoting learn more button" and i get charged, so far, $3.28 per click, for a total of 260 impressions. so it's not what it sound - they dont charge by the click. they still charge by the impressions! i suspect if i use other types of ads, i might get more impression, or even, clicks per se??? i have tried engagement ads, it also seemed pretty expensive (inefficient). i don't want to use a click-bait because what's the point if they click and leave? what's the most efficient ads for promoting the button?