Answer:
40,000
Explanation:
200x 200=40000
I'm pretty sure that's the answer
Answer:
7.8 mm
Explanation:
Wavelength = λ = 710 nm = 710×10⁻⁹ m
Distance between light sources = L = 9 m
Diameter of pinhole = d = 1 mm = 1×10⁻³ m
Rayleigh Criterion

Distance between difraction pattern is 7.8 mm.
I think it is building and managing of irrigation systems