1994 Acura Integra Radiator fan squeaks and inaccurate gas

My a/c wasn't working and I took it to the shop and they told me it was the a/c condenser fan motor. I went ahead and replace it and now the a/c is working but a new problem has come up. My radiator fan is making a squealing noise whenever I put on the a/c. It didn't happen until this week and I have fixed the a/c condenser fan motor last week. What is going on with my radiator fan and how do I fix it? Also, another problem I'm having is that my gas gauge is inaccurate. I have fill my tank all the way up and the gauge only reaches the halfway mark. Then when it hits the empty mark.I refill all the way and that doesn't sound right because it was full but the gauge is messing up my gasoline. What can I do to fix it? Thank you