Answer:
a). 100.2 MHz (typical frequency for FM radio broadcasting)
The wavelength of a frequency of 100.2 Mhz is 2.99m.
b. 1070 kHz (typical frequency for AM radio broadcasting) (assume four significant figures)
The wavelength of a frequency of 1070 khz is 280.3 m. 
c. 835.6 MHz (common frequency used for cell phone communication) 
The wavelength of a frequency of 835.6 Mhz is 0.35m.
Explanation:
The wavelength can be determined by the following equation:
 (1)
  (1)
Where c is the speed of light,  is the wavelength and
 is the wavelength and  is the frequency.
 is the frequency.  
Notice that since it is electromagnetic radiation, equation 1 can be used. Remember that light propagates in the form of an electromagnetic wave. 
<em>a). 100.2 MHz (typical frequency for FM radio broadcasting)</em>
Then,  can be isolated from equation 1:
 can be isolated from equation 1:
 (2)
 (2)
since the value of c is  . It is necessary to express the frequency in units of hertz.
. It is necessary to express the frequency in units of hertz. 
 ⇒
 ⇒ 
But 

Finally, equation 2 can be used:


Hence, the wavelength of a frequency of 100.2 Mhz is 2.99m.
<em>b. 1070 kHz (typical frequency for AM radio broadcasting) (assume four significant figures)</em>
<em> </em>
 ⇒
 ⇒ 
But  

Finally, equation 2 can be used:

 
 
Hence, the wavelength of a frequency of 1070 khz is 280.3 m. 
<em>c. 835.6 MHz (common frequency used for cell phone communication) </em>
 ⇒
 ⇒ 
But  

Finally, equation 2 can be used:

 
 
Hence, the wavelength of a frequency of 835.6 Mhz is 0.35m.