



 
Hi Elena, I would start by sketching a piece of the sine function without axes since the axes described in the question are not in the conventional place. The horizontal units are hours t and the vertical units are degrees of the angle of elevation E. One thing you do know is that the amplitude is 60 degrees. You are told that "the sinusoidal axis is at E=5 degrees" so the horizontal axis is 5 degrees below the conventional xaxis. The maximum elevation is at 12:45 p.m., 45 minutes after noon and the period is 24 hours so the minimum elevation is 12 hours earlier at 12:45 a.m., 45 minutes after midnight. Since t is the number of hours that has elapsed since midnight the vertical axis must cross the horizontal axis at midnight which is 45 minutes (3/4 of an hour) before the minimum elevation. Does this help?  


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