High temperature and little rainfall.
Answer:
Wavelength of the x rays is 
Explanation:
It is given that,
The inter planer spacing between the crystal planes, 
The first-order maximum in the Bragg reflection occurs when the incident and reflected x rays make an angle of 39.4 degrees with the crystal planes. According to the Bragg's condition, the first-order maximum is given by :

n = 1



So, the wavelength of the x rays is
. Hence, this is the required solution.
Answer:
a and d are correct answer
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