Answer:
   52 Hz
Step-by-step explanation:
We can divide the speed by the wavelength to find the number of waves propagated in one second:
   (130 m/s)/(2.5 m/wave) = 52 waves/s
The SI unit of frequency is the Hertz, equal to one cycle per second.
The frequency of this wave is 52 Hz.
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<em>Additional comment</em>
The use of the unit Hz to signify frequency was adopted in 1933, but did not replace the unit "cycles per second" (CPS) until a number of years later.
 
        
             
        
        
        
It would be (-5, 15) or b.
        
             
        
        
        
Answer:
<em>72,000cm³</em>
Step-by-step explanation:
Volume of the rectangular tank = Length *  Width * Height
Given 
Length = 50cm
Width = 30cm
Height = 60cm
Get the volume:
Volume = 50*30*60
Volume = 90,000cm³
Hence the volume of the rectangular tank is 90,000cm³.
If 1/5 of the volume of water was transferred to another tank, the volume transferred will be:
Amount transferred = 1/5 * 90,000
Amount transferred = 18000cm³
Amount left in the tank = 90,000 - 18,000
<em>Amount of water left in the tank = 72,000cm³</em>
 
        
             
        
        
        
Answer: 2.236
Step-by-step explanation: The square root of 5 is expressed as √5 in the radical form and as (5)½ or (5)0.5 in the exponent form. The square root of 5 rounded up to 5 decimal places is 2.23607. It is the positive solution of the equation x2 = 5.