Answer:
The formation of a rainbow is more a demonstration of the wave-like behavior of light.
Explanation:
A rainbow is caused by the interaction of sunlight with atmospheric conditions. A rainbow formation results from the refraction and reflection of light due to changes in the light's wavelength direction.  Naturally, light enters a water droplet, slowing down and bending as it goes from air to denser water in a refraction as if "bent." Then light reflects off the inside of the droplet, separating into its component wavelengths or colors.  With light exiting from the droplet, a rainbow is formed.
 
        
             
        
        
        
Explanation:
The distance that a car travels down the interstate  can be calculated with the following formula:
Distance = Speed x Time
(A) Speed of the car, v = 70 miles per hour = 31.29 m/s
Time, d = 6 hours = 21600 s
Distance = Speed x Time
D = 31.29 m/s × 21600 s 
D = 675864 meters
or

(b) Time, d = 10 hours = 36000 s
Distance = Speed x Time
D = 31.29 m/s × 36000 s
D = 1126440 meters
or

(c) Time, d = 15 hours = 54000 s
Distance = Speed x Time
D = 31.29 m/s × 54000 s
D = 1689660 meters
or

Hence, this is the required solution.
 
        
             
        
        
        
Answer: The width of bands will be 2λ
Explanation: Please see the attachments below