What is the relationship between politically affiliated and independent PACs with regard to how they are regulated and how much they spend?

Politically Affiliated PACs are only allowed to make contrition up to a maximum of  $2,000 to a candidate per election campaign

Independent PAC do not have a maximum amount of contribution, but that contribution cannot be send directly to candidate's campaign.  But, it can be allocated to other things that might help the election. For example, the money from independent PAC could be sent to a certain news organization to give favorable reporting's toward the candidate.

  b.

there are isolated pockets of farming, generally around rivers and oases, which are used for irrigation.

we need an attachment to see what you are talking about.