1) A student is standing on the east side of a building and notices that it casts no shadow. One hour later, she notices that the shadow of the building is about 3 feet long. Approx. how high is the building she is standing next to? In this problem I honestly just dont know where to start. We've gone over gnomons in the class which I know use shadows to make projections, but the question is on the building and not what position the sun is in, as the gnomon is used for. I know there must be an equation to use for this but I cant find one in the textbook given. Any help on an equation I can use to figure this out? --------------- 2. One of the major scientific objections to Copernicus's theory was the absence of stellar parallax. Suppose that the most accurate measurement of the angles that defined the position of a star was good to 1/2 degrees in the time of Copernicus. How far away would the stars have to be compared to the earth-sun distance to explain the absence of observed stellar parallax in Copernicus's theory? Is there an equation for figuring this out as well? I'm not trying to have anyone do this for me but I have absolutely no clue where to start on these two problems.