To find a percentage (ex:on a test) you take the number you got right and divide it by the number there is. Then you multiply by 100. For EX: You got 56 out of 60 on a test. You can write it as a fraction (56/60) then divide.
It is a government in which the supreme power was elected by "the people" and "the people" have the power to impeach, or overthrow, that government if it becomes destructive to their rights.