Answer:
Night vision is when you can see in the dark or at night like owls
Explanation:
 
        
                    
             
        
        
        
Answer:
a)  
b) 
Explanation:
Given:
String vibrates transversely fourth dynamic, thus n = 4
mass of the string, m = 13.7 g = 13.7 × 10⁻¹³ kg
Tension in the string, T = 8.39 N
Length of the string, L = 1.87 m
a) we know

where,
 = wavelength
 = wavelength
on substituting the values, we get
 
or
 
b) Speed of the wave (v) in the string is given as:

also,

equating both the formula for 'v' we get,

on substituting the values, we get

or

or

 
        
             
        
        
        
Explanation:
(a) Frequency of radar energy, 
The relation between frequency and wavelength is given by :




or

(b) If wavelength, 




or
f = 1.2 GHz
Hence, this is the required solution.
 
        
             
        
        
        
So we want to explain the effects of time dilation. In theory of relativity time dilation is the difference of elapsed time between two events when measured by two observers who are moving relatively to each other. A clock of an observer that is standing still in an inertial frame of reference is going to measure a different time of an event than the clock of an observer that is moving with some velocity with respect to the inertial reference frame that is not moving. In a nutshell, the moving clock is ticking slower than the clock that is standing still.  
        
                    
             
        
        
        
Answer: $85.80
Explanation: 100kg is equalvilent to 220 lbs, then you multiply 220 by .39 and then you have your answer :)