Yes, they do, but their affect is minimal. Magnets with their magnet fields affect inductors profoundly, but don't do to much to capacitors.
No, there are no magnets in a normal mechanical piano.
it will lose its magnetism OR it will get weaker
Here's one possibility ... no guarantee: Radios of that era used large-value electrolytic capacitors in their power supply filters. These capacitors can deteriorate over time, allowing AC-ripple out of the power supply, which is then clearly audible in the audio stages. Take the radio to a TV-repair shop or a friend familiar with electronics construction, and ask them to replace the electrolytic capacitors in the power supply.
In radios that aren't solid state, and use variable capacitors for tuning, the air-dielectric variable capacitor is the almost universal choice for radio frequency applications. More information on air variable capacitors is available at www.orenelliottproducts.com.
Electric Guitars,
yes i tried and different liquids affect the strength of magnets
no
yes temp does affect the strength of magnets. The cooler the magnet the stronger it gets.
x
No.
yes it can
Magnets do not affect plants in any way
They affect the magnetism so yes
A permanent magnet can affect magnets and electromagnets.
If an electromagnet is close enough, it will either attract or repel other magnets.
I don't knwo
yes