Question

What are the wavelengths for x-rays with frequency 3 x 10^18?

Answer 1

For this problem, we can use the formula $wavelength= \frac{c}{f}$ in which c is the speed of light, and f is the frequency. 
The speed of light is $3.00* 10^{8} m/s$. 
Plug these values in the equation:$wavelength = \frac{3.00* 10^{8} }{3* 10^18}$
and you will get:
wavelength= 1*$10^{-10}$