The galactic center, meaning the center of the milky way contains millions of stars all of various types
Answer: he expected to find no darkening of the film all because it hadn't been exposed to sunlight yet.
As concentrated energy is used to do WORK, it becomes spread out.
The universe is made up of constant supply of energy. Energy is use to do work; the usefulness of energy is been degraded as it is been used to carry out work. For instance, the energy in petrol is used to run motor vehicles, the process result in the conversion of the chemical energy in the petrol to heat energy. The heat energy that is produced can not be easily gathered and used again, thus, the usefulness of that heat energy has been degraded.
