Federation Play Situations

[LJ_966]

Alright, guys...an old dog still gets confused once in a while, these have been confusing me since the 1st day I read the rules, so help me out:

1.
A1 throws a fwd. pass which is tipped by B1, A2 catches this pass behind the NZ. A2 then throws a fwd. pass downfield to eligible A3 who pushes safety B2 to the ground. A3 catches the pass.

Pass interference restrictions end for all B players when A touches the FIRST PASS. Restrictions end for all A players when B touches "the pass," or "last pass if more than one." Has A3 commited pass interference? I think I know the answer...but maybe someone's got a handy way of remebering this rule...

2.
While a free kick or scrimmage kick is in flight, R1 gives a valid fair catch signal. R2 then also gives a valid fair catch signal. R2 catches the kick and the ball becomes dead. But did R2 make a fair catch? Or can only one R player make a "fair catch"...with the according choices that follow one? In other words, after a valid or invalid FC signal has been given by any member of R, the ball will become dead when possessed by any R player. But, if 5 R's give a valid FC signal, perhaps even simultaneously, would each be able to make a 'fair catch' by rule?