AWR STATIC Baselines

Hi,

We have a 2 NODE 19.19 RAC database 

We are planning to implment AWR baselines so that we have a baseline to compare any performance issue to and have a couple of questions in terms of best practices when it comes to having STATIS AWR Baselines

Q#1. Since we have RAC do we need to create a STATIC baseline for each instance or can we create a RAC DB baseline that automatically  will include both instances? If yes, how would we create such a baseline? 

Q#2. When creating STATIC AWR baselines, assuming the snapshot interval is an hour, should we create a static baseline spanning 24 snapshots