Answer:
a) 
b) 
Explanation:
From the question we are told that:
Width of diffraction grating 
Width of silt 
Distance 
a)
Generally the grafting element is the distance b/w the silts

Therefore the grafting element is

b)
Generally the equation for diffraction state is mathematically given by

Since

Therefore



Therefore orders observed with
is

Answer:
u can use a calculator to answer that question thats ur only hint
Explanation:
Hi, earth and the sun would be your answer.