'Climatic variations' and 'Human activities' can be regarded as the two main causes of desertification. removal of the natural vegetation cover(by taking too much fuel wood), agricultural activities in the vulnerable ecosystems of arid and semi-arid areas, which are thus strained beyond their capacity.
Answer:
So the wavelength of light is 1015.7 nm
Explanation:
From Wein's displacement law, we can write the following formula;
here,
is the wavelength of maximum radiation in meters
T is the absolute temperature (in Kelvin) for maximum radiation
K is the constant has a value of 
Given here, T = 2853 K
And we need to find 
Putting the values in formula



7. B
8. D
9. A
Hope that helps out man!
~Ressedue~
__________
The answer is b
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