I think its d because lifting it would make the chemical swish around and that will make it so you cant get the right measurement. hope this helps :)
Complete Question
The complete question is shown on the first uploaded image
Answer:
The components of reaction at the fixed support are
,
,
,
,
, 
Explanation:
Looking at the diagram uploaded we see that there are two forces acting along the x-axis on the fixed support
These force are 400 N and
[ i.e the reactive force of 400 N ]
Hence the sum of forces along the x axis is mathematically represented as

=> 
Looking at the diagram uploaded we see that there are two forces acting along the y-axis on the fixed support
These force are 500 N and
[ i.e the force acting along the same direction with 500 N ]
Hence the sum of forces along the x axis is mathematically represented as

=> 
Looking at the diagram uploaded we see that there are two forces acting along the z-axis on the fixed support
These force are 600 N and
[ i.e the reactive force of 600 N ]
Hence the sum of forces along the x axis is mathematically represented as

=> 
Generally taking moment about A along the x-axis we have that

=> 
Generally taking moment about A along the y-axis we have that

=> 
Generally taking moment about A along the z-axis we have that

=> 
Acceleration, a = (v - u)/t
where v is the final velocity, u is the initial velocity, and t is the time.
This formula on a velocity time graph represents the slope of the graph.
Answer:
Potential energy is stored energy and the energy of position––gravitational energy. There are several forms of potential energy. Electrical Energy is the movement of electrical charges. Everything is made of tiny particles called atoms.
Answer:
Explanation:
a ) The velocity will never be zero . The velocity will be minimum at the highest point of projectile, which will be equal to the horizontal component of the initial velocity.
b ) The velocity will be minimum when its kinetic energy will be minimum . Kinetic energy will be minimum when its potential energy will be maximum.
Its potential energy will be maximum at the highest point so velocity will be minimum at the highest point.
c ) Velocity will never be the same as initial velocity because constant force of gravitation is acting on the projectile all the time.
d ) At the moment when the projectile returns back and hits the ground, the speed becomes equal to the initial speed ( at t = 0 ) because its kinetic energy becomes the same as initial energy , the height becoming zero.