Intensity of red laser vs blue laser

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1. Homework Statement :
Consider two lasers, one blue and one red. Which of the two lasers has the higher intensity?


2. these are my choices:
The blue one.
Cannot be decided based on the information given.
The red one.


3. The Attempt at a Solution :
The difference between these two lasers is their wavelength. Red has a higher wavelength than blue. Both have the same velocity, so red also has a lower frequency than blue (because v = wavelength * frequency). However, intensity depends on amplitude. (this is where I'm not sure) Amplitude does not depend on wavelength even though the displacement depends on both amplitude and wavelength, so we cannot decide with the given information.

am i right or totally off?
 
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You are completely right.
 
I also think the intensity is given by the amplitude.. Just like volume in sound is given by it.
 
To solve this, I first used the units to work out that a= m* a/m, i.e. t=z/λ. This would allow you to determine the time duration within an interval section by section and then add this to the previous ones to obtain the age of the respective layer. However, this would require a constant thickness per year for each interval. However, since this is most likely not the case, my next consideration was that the age must be the integral of a 1/λ(z) function, which I cannot model.
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