Fbads - some questions, cpc, 301 redirect etc.

Hello!

I have some questions about fbads.
1. Allow only mobile traffic + news feed is a good way to lower CPC?
2. If I set no limit CPC it might go as low as If I'II set limit? Like If I'II get high CTR or something.
3. Can comments/reactions lower the CPC?
4. If I'II use Freenom to create new domain for BH its better to use 301 redirect to my LP or just do frame redirect? I hear that 301 redirect is restricted on fbads
5. If I don't specify my target audience just set age + gender I might get better CPC because I wasn't too specified?

Probably nobody will answer you those questions because that's take a lot of $ and afford to find out the real answear. Just invest and test all options.