hey, I want to upload a new landpage, but I don't know if this is alright with Adsense : http://pecansms.googlepages.com/index.html
Not at the moment it's not...DON'T put adsense on a page that has nothing on it. Put real content on it first.
Content is very important in terms of applying adsense on it. only thing is that landing page has to have a unique content on it.
Read the adsense TOS before asking questions. That site is not good for adsense. They might ban you if they found out about your site.
It is better if you add in the content then only ask for review. The placement is inter-related with the content placement. You need to balance it.