The equation you need to use is

where Q is the charge in C, I is the current in Amps and T is the time in seconds.
So we have T = 60s
I =

A
let's work out Q

C
this is the total charge passing a point in a minute so divide by the charge of one electron (

) to find the number of electrons passing the point in a minute which equals
Answer:
v = 2,99913 10⁸ m / s
Explanation:
The velocity of propagation of a wave is
v = λ f
in the case of an electromagnetic wave in a vacuum the speed that speed of light
v = c
When the wave reaches a material medium, it is transmitted through a resonant type process, whereby the molecules of the medium vibrate at the same frequency as the wave, as the speed of the wave decreases the only way that they remain the relationship is that the donut length changes in the material medium
λ = λ₀ / n
where n is the index of refraction of the material medium.
Therefore the expression is
v =
Let's look for the frequency of blue light in a vacuum
f =
f =
f = 6.667 10¹⁴ Hz
the refractive index of air is tabulated
n = 1,00029
let's calculate
v =
450 10-9 / 1,00029 6,667 1014
v = 2,99913 10⁸ m / s
we can see that the decrease in speed is very small
195 is the rounded atomic atomic mass of platinum