Blasts are used for communicating different signals when vessels move.When a boat is leaving, a long blast, at intervals of not more than two minutes, is used for alerting other vessels, when a boat is sailing. When leaving the dock, only a single prolonged blast is used for indicating others, that you are leaving.
That will be A melting a substance that's because the rest are examples of chemical changes and also its the same thing but in a different form.
If you are talking about gravitational potential energy, then the ONLY way to either increase OR decrease it is to raise or lower your height. The higher you are off the ground the greater your PE, the closer you are to the ground, the lower your PE
The right answer is B. It is a reference point. Because it will let you measure the distance made which is the lenght from the starting point to the current point of position of the life form.
Choice-'b' says the formula for kinetic energy in words.
KE = (1/2) · (M) · (S²)