Question

What is the wavelength for light of frequency `1xx10^-13*s`?

Answer 1

WE use the relationship `c=nuxxlambda`

Explanation:

And thus `lambda=c/nu=(3xx10^8*m*s^-1)/nu`

And if `nu=1.00xx10^13*s^-1`.

`lambda=(3xx10^8*m*cancel(s^-1))/(1.00xx10^13*cancel(s^-1))=3xx10^-5*m`

...and this is in the radiowave region.....

I leave it to you to calculate the other wavelengths....