Answer: 
 "The distance between crests is 3 cm." 
Explanation:
If he writes down "The distance between crests is 3 cm." 
That means he is describing the wavelength of a wave and not longitudinal wave. He ought to write something about " direction "
Longitudinal waves are waves in which the displacement of the medium is in the same direction as, or parallel to, the direction of propagation of the wave. While 
Wavelength is the distance between the two successfully Crest or trough 
 
        
             
        
        
        
Answer:
7/150
Explanation:
The following data were obtained from the question:
Object distance (u) = 75cm
Image distance (v) = 3.5cm
Magnification (M) =..? 
Magnification is simply defined as:
Magnification (M) = Image distance (v)/ object distance (u)
M = v /u
With the above formula, we can obtain the magnification of the image as follow:
M = v/u
M = 3.5/75
M = 7/150
Therefore, the magnification of the image is 7/150.
 
        
             
        
        
        
Answer:
S = 27500J / 308.15molK
Explanation:
Entropy measures the degree of disorganization of a system. It is measured in the entropy change that is equal to the heat exchanged divided by the temperature at which the process occurs.
S2-S1 = Q / T
S = entropy
Q = heat = 27.5 kJ / mol * 1000J / 1KJ = 27500J / mol
T = temperature = 35 + 273.15 = 308.15K
units = J / molK
S = 27500J / 308.15molK
 
        
             
        
        
        
This version of Einstein’s equation is often used directly to find what value? E = ∆mc2
Answer: This version of Einstein’s equation is often used directly to find the mass that is lost in a fusion reaction. Therefore the correct answer to this question is answer choice C).
I hope it helps, Regards.
        
                    
             
        
        
        
Answer:
Aluminium
Explanation:
Aluminium has the least resistance since It has 3 free electrons per atom. Its resistivity is low compared to other metals provided in the choices (gold, nichrome, tungsten). Low resistivity of metals means a high conductance of the metal referred to.