To solve this problem we will apply the concepts related to Reyleigh's criteria. Here the resolution of the eye is defined as 1.22 times the wavelength over the diameter of the eye. Mathematically this is,

Here,
D is diameter of the eye


The angle that relates the distance between the lights and the distance to the lamp is given by,

For small angle, 
Here,
d = Distance between lights
L = Distance from eye to lamp
For small angle 
Therefore,



Therefore the distance is 5.367km.
If you mean like electromagnetic waves then, Mico waves, UV rays, and infrared waves
Answer:
It’s 18.0 m/s
Explanation:
Use acceleration formula then plug in 9.8 and 1.84s
A) 50 cm
B) 10000 cm/s
Explanation
Step 1
A)
If you know the distance between nodes and antinodes then use this equation:

then, let

now, replace to find the wavelength

so, the wavelength is
A) 50 cm
Step 2
The speed of a wave can be found using the equation

or velocity = wavelength x frequency,
then,let

replace and evaluate

so
B) 10000 cm/s
I hope this helps you