Answer:
Technician B is correct
Explanation:
Freezing is a method of conversion of substance in its liquid state to solid state. It is the process by which a liquid substance changes to a solid at a particular temperature. 
Increasing the pressure and decreasing the temperature of a liquid increases its freezing point. For example, in other to freeze water i.e to change water to ice, it has to be kept in a fridge at a temperature lower than the temperature of the water. The essence of covering the fridge after placing the water in the fridge is to increase the pressure of the liquid hence increasing its freezing rate.
Based on the above explanation, it can be concluded that technician B is correct.
 
        
             
        
        
        
No force is necessary to keep a moving object moving (in a straight line at a constant speed).
        
             
        
        
        
Answer:
  t_{out} =  t_{in},      t_{out} =
 t_{in},      t_{out} = 
Explanation:
This in a relative velocity exercise in one dimension,
let's start with the swimmer going downstream
its speed is
          
The subscripts are s for the swimmer, r for the river and g for the Earth
with the velocity constant we can use the relations of uniform motion
             = D /
 = D / 
            D = v_{sg1}  t_{out}
now let's analyze when the swimmer turns around and returns to the starting point
         
           = D /
 = D / 
          D = v_{sg 2}  t_{in}
with the distance is the same we can equalize
            
           t_{out} =  t_{in}
            t_{out} =  t_{in}
 t_{in}
This must be the answer since the return time is known. If you want to delete this time
             t_{in}= D / 
we substitute
             t_{out} = \frac{v_s - v_r}{v_s+v_r} ()
             t_{out} = 
 
        
             
        
        
        
The answers A, this is because Ice is originally water and when water goes below it's freezing point it turns into ice