How do you open the gas tank on a Mazda 3 2021?

My car is pretty old, so it doesn’t have bluetooth. The adapter I had to plug my phone into my car died, and in the meantime, I’ve been listening to the radio. The problem is there is so much static when I listen to the radio, and it never happened with my phone, so I know it’s not the speakers. How do I fix radio static in my car?

I bought a used car a few months ago that has been modified with a turbo and some additional parts. It’s a blast to drive, but the turbo hasn’t been working correctly. How much does it typically cost to fix a car’s turbo?

Is there any easy way to know which type of car battery you have? I think my battery’s dying, so I need to get it replaced. Before I do, I should probably know which battery to ask for.