Answer:
Melting
Explanation:
The process of a solid becoming a liquid is called melting. (an older term that you may see sometimes is fusion). The opposite process, a liquid becoming a solid, is called solidification. For any pure substance, the temperature at which melting occurs—known as the melting point—is a characteristic of that substance.
Both positive work and negative work have meaning: Positive work follows when the force has a component parallel to the displacement. Positive work adds energy to a system. Negative work follows when the force has a component opposite or against the displacement.
Answer:
V(t1-t0)
Explanation:
Moving 'uniformly' means constant velocity (speed). the formula for constant speed motion is 
=( change in position/ change in time)
where,
V is speed
given in the statement :
change in time = t = t1-t0
let the constant speed be ' V '
disance = X = X1-X0
applying the above mentioned formula: V = 
V = X/t
X = Vt
the distance X1-X0 = Vt =V(t1-t0)
Refraction is the change in direction of a wave.
Diffraction is the bending of a wave around a barrier.
