Undergrad Calculation of the absorption coefficient for GaAs

[yeyintkoko]

Anyone can explain me this example?

I substitute value for
e = 1.602*10^-19;
m₀ = 9.1*10^-31;
pi = 3.14;
and calculated value for μ_av in matlab.
I received 1.7104*10^-19. But in exam this value is 0.68*10^-25.
What is i wrong?
please help me.
Thank you.

 

[mfb]

WolframAlpha calculates 6.84*10^-29 Cm. Perfect confusion!

 

[yeyintkoko]

Thanks you mfb.
Now i known what is wrong.
Unit error. :)
Thanks you again!