I believe the correct answer would be kimberlite. Diamonds are usually found in pipes 50 to 200 m across made of kimberlite. It is an igneous rock that is known to contain traces of diamonds. It is named base on the town where it was discovered which is Kimberley, South Africa.
The correct answer is B. Nitrogen
Yes, it is true, both mass spectrometry and infrared spectroscopy involve interaction of molecules with electromagnetic waves. ;Mass spectrometry method is used to determine the mass of a substance while infrared spectroscopy is used to determine the functional groups in molecules. Both methods involve the analysis of electromagnetic light interaction with molecules.
Explanation:
(a) Frequency of radar energy, 
The relation between frequency and wavelength is given by :
or
(b) If wavelength, 
or
f = 1.2 GHz
Hence, this is the required solution.
B acid rain in an area kills fish in a lake
