Electromagnetic waves do not require a medium to travel through. They can travel through empty space or matter.
Answer:

Explanation:
We first identify the elements of this simple harmonic motion:
The amplitude A is 8.8cm, because it's the maximum distance the mass can go away from the equilibrium point. In meters, it is equivalent to 0.088m.
The angular frequency ω can be calculated with the formula:

Where k is the spring constant and m is the mass of the particle.
Now, since the spring starts stretched at its maximum, the appropriate function to use is the positive cosine in the equation of simple harmonic motion:

Finally, the equation of the motion of the system is:
or

I hope I am correct my Science teacher said this was the answer to your question
1. GPE
2. KE
3. KE
4. KE
5. Both
6. Both
7. Neither
8. Neither
Alright I think these should be right ;)