Day and night are caused by
a. the tilt of earth's axis.
b. earth's revolution around the sun.
c. eclipses.
d. earth's rotation on its axis.

pe = weightxheight = 2000x1000=2,000,000joules

  the unit of the measure =

explanation:

  the property that is quantified by the energy needed per of material to raise the temperature by one.

  si unit of energy = joule (j)

  si unit of temperature = kelvin (k)

  si unit of mass of material = kilogram (kg)

the property that is quantified by the energy needed per of material to raise the temperature by one is called specific heat.

the unit of specific heat is