So, I’m assuming that we’re treating light as a propagating wave. 
Amplitude measures the amount of energy transported by a wave, thus amplitude squared is directly proportional to the light’s energy. The higher the amplitude, the higher the energy. 
Energy is also directly proportional to the frequency of a wave, the higher the frequency, the higher the energy. 
I took my second answer from the formula below:
E=cf
        
             
        
        
        
Answer:
mass of one atom is measured in the unit of 1 amu
Explanation:
As we know that the mass of one atom is very small and it is of order of 
here we know that 1 amu is defined as 1/12 part of mass of 1 atom of C-12 isotope
so here we will have

so here we can say that mass of one atom is measured in the unit of 1 amu
 
        
             
        
        
        
A. Ask other people for their opinion. :)
        
             
        
        
        
Answer:
 28.23 years
Explanation:
I = 1100 A
L = 230 km = 230, 000 m
diameter = 2 cm 
radius, r = 1 cm = 0.01 m 
Area, A = 3.14 x 0.01 x 0.01 = 3.14 x 10^-4 m^2
n = 8.5 x 10^28 per cubic metre
Use the relation
I = n e A vd
vd = I / n e A
vd = 1100 / (8.5 x 10^28 x 1.6 x 10^-19 x 3.14 x 10^-4)
vd = 2.58 x 10^-4 m/s
Let time taken is t. 
Distance = velocity x time 
t = distance / velocity = L / vd
t = 230000 / (2.58 x 10^-4) = 8.91 x 10^8 second
t = 28.23 years