A global positioning satelite transmits a radio wave with a wavelength of 19 cm. What is the frequncy of the radio wave ?

which means that your wave will have a frequency of

v=1.6* 10^9Hz

Step-by-step explanation; here's  some examples i had from my class.

In simple terms, the inverse relationship that exists between frequency and wavelength tells you that high frequency waves will have short wavelengths, and low frequency waves will have long wavelengths

The wavelength used by the satellite fall in the relatively long category, which means that you can expect it to have a relatively high frequency.

Before doing any calculations, notice that the speed of light is given in meters per second. This means that you will need to convert the wavelength of the wave from centimeters to meters in order to make sure that the units cancel out.

Because frequency and wavelength are related by a constant (c) the energy can also be written in terms of wavelength: E = h · c / λ. When the energy increases the wavelength decreases and vice versa. That is, energy in inversely proportional to wavelength.