How much is the UC student association fee?

Excuse me, could you please clarify for me the cost of the UC student association fee? I'm trying to budget for my upcoming semester and would like to ensure that I have all the necessary fees accounted for. Is the student association fee a one-time payment or does it need to be paid each semester? Additionally, is there any way to find out if there are any discounts or waivers available for the fee? I appreciate your assistance in this matter.