Answer:
The wavelength of the light is
.
Explanation:
Given that,
Distance between the slit centers d= 1.2 mm
Distance between constructive fringes 
Distance between fringe and screen D= 5 m
We need to calculate the wavelength
Using formula of width

Put the value into the formula




Hence, The wavelength of the light is
.
Answer:
82 degrees
Explanation:
consider your staying point to be the center of a circle. this center has the coordinates (0, 0).
the radius of the circle is the distance you walked East (14 miles).
I assume your teacher means as "angle of displacement" the angle between the East-West line going through your starting point and the direct line from your starting point to your current position.
then the 100 miles North is tan(displacement angle)×14.
as it is the same, if you first went North and then East, or the other way around. you end up at the same point, with the same coordinates.
so, again.
100 = 14×tan(angle)
tan(angle) = 100/14 = 50/7 = 7.142857...
the displacement angle is then 82 degrees.
It would be autotroph and hetrotroph