I'd say potential/kinetic energy.
Answer:
Explanation:
Givens
The frequency is defined by
Where 
is the speed of the wave in the string and 
is its wave length.
The wave length is defined as 
Now, to find the speed, we need the tension of the wire and its linear mass density
Where 
and the tension is defined as 
Replacing this value, the speed is
Then, we replace the speed and the wave length in the first equation
Therefore, the frequency is
Almost right. protons are positive and electrons are negative. so when you run the balloon on your hair, electrons are transferred between them (i’m not sure which direction) and now one is positively charged as it lost negative particles and one is negative as it gained negative particles (electrons). opposite charges attract
ANSWER: NATURE
EXPLAINTION:
Incompressible. Compressibility is determine by the amount of space between particles in each state.
