Answer:

Explanation:
The correct equation follows the law of conservation of energy where kinetic energy is all transformed to potential energy, since we know that kinetic energy is expressed as
while potential energy is mgh where m is the mass of the object, v is the velocity or speed of the object, g is acceleration due to gravity and h is the vertical height. Therefore, relating the two equations we should have 
The answer is 8.
Hope I helped.
Answer:
Velocity: +ve, Acceleration: -ve
Explanation:
Here I've considered downward direction as positive direction.
Answer:
to check for errors.
Explanation:
since some of the components of the scale are metallic, they are prone to rusting which would cause error in reading of the scale so there is organized checking if the scale to correct that.
hope it helps .
Changes in state of matter would be a physical change to whatever it is that you are changing so I think it would be B.Molecules because in order for something to change the molecules have to be moving apart from one another but I maybe wrong depending on what it is your looking at