1. Record several more measures of angles A and B in the spreadsheet.[br]2. What happens to the individual angle measures when a vertex is dragged? What happens to the [i]sum[/i] of the acute angles when a vertex is dragged?  [br]3. Find sin(A) and cos(B) in the spreadsheet (FILL DOWN within each column). What do you notice? Can you explain why this is so?[br]4. [i]Optional: [/i]Drag the left bar of the spreadsheet to reveal columns F and G and FILL DOWN in those columns. What is the result for [math]sin^2A+cos^2A[/math]? Why do you think this occurs?