Explanation:
Simply, shake the boxes. The box that is difficult to shake will be the sand and the box that will be easier will be the feathers.
 
        
             
        
        
        
The answer is B, or endoplasmic reticulum.
        
                    
             
        
        
        
Answer:
How long would it take a machine to do 13,000 joules of work if the power rating ... An object gains 15 joules of potential energy as it is lifted vertically 5.0 meters. ... As the time required to do a given quantity of work decreases, the power ... How much work is being done to the system by the person of the sled moves 10 m?
 
        
             
        
        
        
False............ It is in both directions in the form of centri-petal & fugal towards inwards and outwards respectively....
        
             
        
        
        
f = frequency of the sound wave = 680 hertz 
λ = wavelength of the sound wave = 0.5 meters 
v = speed of sound wave 
we know that , speed of sound wave is given as 
speed of sound wave = frequency of sound wave x wavelength of sound wave 
v = f λ
inserting the above values in the formula above 
v = (680 hertz) (0.5 meters)
v = 340 meter/second 
hence the speed of sound wave comes out to be 340 meter/second