So as you may know atoms are neutral because the number of protons (+ charge) and the number of electrons( - charge) are the same so they cancel out. When a valence electron leaves an atom it will have a +1 charge because there is one less negative than positives or there is one more positive than negatives since a negative electron left. If a valence electron is added a -1 charge because there is now one more negative than positive!!!
hope that helps!!
No they say "Watch out it's the fuzz"
To solve the problem it is necessary to use the concepts related to the calculation of periods by means of a spring constant.
We know that by Hooke's law

Where,
k = Spring constant
x = Displacement
Re-arrange to find k,




Perioricity in an elastic body is defined by

Where,
m = Mass
k = Spring constant


Therefore the period of the oscillations is 0.685s
Here are the ones that I know about
and can think of just now:
-- wind
-- solar
-- nuclear
-- tidal
-- hydro
-- geothermal
-- biomass