Question about Facebook shares vs. Likes on site

I have an amazon affiliate site, so naturally I focused on making a facebook page for the site, that I will sometimes use to promote posts when I write new ones.
I have a couple of questions however:

1. What is more effective in terms of ranking- is it just the number of overall shares that you get from fb to your various posts on your site- or a large number of likes on your facebook website page?
2. I have various posts with various number of different shares- for example 1 post with 1k shares, 1 post with just 50 shares. I'm guessing Google takes into account this, and the 1k shares will have a greater effect on that post compared to the one with less shares, correct?

Thanks

1. If someone shares your post, they'll almost certainly like it too I think, the number of overall shares is more effective.
2. Yes