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:
convex lens because it makes parallel light rays passing through it bends inwards and meets convex at a spot just beyond the lens known as the focal point
Answer:
therefore normal reaction on the driver from the seat when the car passes through the bottom of the valley= 1520.55 N
Explanation:
let speed be v
at top of hill
mg-N = mv^2/R ( N=0 at the top of the hill)
==> mg=mv^2/R
at bottom
N-mg=mv^2/R
therefore,
N = 2mg = 2*77.8*9.81= 1520.55 N
therefore normal reaction on the driver from the seat when the car passes through the bottom of the valley= 1520.55 N
I think the correct answer is D: Potential Energy.