Answer
2.08 pm
Work Step by Step
Speed, c = $2.997925\times10^{8}ms^{-1}$
Frequency, ν = $1.44\times10^{20} s^{-1}$
Wavelength, λ = c/ν = $\frac{2.997925\times10^{8}ms^{-1}}{1.44\times10^{20} s^{-1}}$ = $2.08\times10^{-12}m$ = 2.08 picometers ( value of the prefix 'pico' is $10^{-12}$)
