When billy flips a coin, it appears to be different shapes as it rotates in the air. sometimes it looks like a circle, sometimes more oval, and, when flat, like a thin sliver. by using which perceptual rule does billy know that although his perception of the penny's shape may change, it never actually changes shape?

you should try adrenaline. it kicks in in situations like this.

world war i had a devastating effect on german-americans and their cultural heritage. up until that point   german-americans, as a group, had been spared much of the discrimination, abuse, rejection, collective mistrust experienced by so many different racial and ethnic groups in the history of the united states. indeed, over the years, they had been viewed as a well integrated and esteemed part of american society. all of this change with the outbreak of war.