Answer:
Pascal's principle, also called Pascal's law, in fluid (gas or liquid) mechanics, statement that, in a fluid at rest in a closed container, a pressure change in one part is transmitted without loss to every portion of the fluid and to the walls of the container
 
        
             
        
        
        
Answer:
its 1/2 the mass of the object times by its velocity ^ 2
 
        
             
        
        
        
Answer:
C. Atoms
Explanation:
The basic unit of matter and the smallest, indivisible unit of a chemical element. It comprises a nucleus (neutrons + protons) that is surrounded by a cloud of electrons.
 
        
             
        
        
        
Using the principle of floatation.
u = w............(a)
Upthrust of fluid is equal to the weight of the object.
Let the volume of the wood be V.
The upthrust u, is related to the volume submerged in water, and that is 1/5 of it volume, that is (1/5)V = 0.2V
Formula for upthrust, u = vdg
where v = volume of fluid displaced
d = density of fluid
g = acceleration due to gravity
weight, w = mg
where m = mass
g = acceleration due to gravity 
From (a)
                     u = w
                 vdg =  mg      Cancel out g
                   vd  =  m
 
The v  is equal to 0.2V, which is the submerged volume. Notice that the small letter v is volume of fluid displaced, and capital V is the volume of the solid. 
d is density of fluid which is water in this case, 1000 kg/m³
         0.2V * 1000 =  m
           200V =  m
Hence the mass of the object is  200V  kg.
But Density of solid =  Mass of solid / Volume of solid
                                 =    200V / V
                                 =    200 kg/m³
Density of solid = 200 kg/m³