Why is electricity considered a secondary source of energy

Inadequate stores control is not an obstacle to effective work order system. (clo4) a)-true b)-false

Asteam is contained in a rigid tank with a volume of 1 m3. initially, the pressure and temperature are 7 bar and 500 oc, respectively. the temperature drops due to cooling process. determine: (1) the temperature at which condensation begins in °c, (2) the fraction of the total mass that has condensed when the pressure decreased to 0.5 bar. (3) the volume in m3 occupied by saturated liquid at the final state?

When subject to a steady load (within elastic range) over a long period of time, what is the major difference in material behavoir between steel and plastic?