1) 
The capacitance of a parallel-plate capacitor is given by:

where
is the vacuum permittivity
A is the area of each plate
d is the distance between the plates
Here, the radius of each plate is

so the area is

While the separation between the plates is

So the capacitance is

And now we can find the energy stored,which is given by:

2) 0.71 J/m^3
The magnitude of the electric field is given by

and the energy density of the electric field is given by

and using
, we find

VF=0
Vi=60mph
T=4.0s
you need to convert hours to seconds... so you do there is 60 minutes in an hour and there is 60 seconds in a minute so you do 60*3=180
180/4.0=45m/s^2
The largest transition metal is copernicium with 112 protons.
I think it is 5% hope this helped