[list=1][*]Using your page’s general settings, press the “Show Axis” and “Show Grid” buttons if they are not already active.[/*][*]From the “Circle: Center & Radius” section, create a circle with the center point at (0,0) and a radius of 1[/*][*]Name the center point O. This will be your unit circle.[br][/*][*]In the Algebra input bar, type k = 0 to create a numeric variable k. This value will later be changed randomly.[/*][*]In the input bar, define an angle a in degrees by writing a = k°. This ensures that whenever k changes, the angle a also changes accordingly.[br][/*][*]Using the input bar again, create a point on the unit circle: A = (cos(a), sin(a)). [/*][*]Use the “Segment” tool to draw the segment OA and name it r.[br][/*][*]Create a point B where the unit circle intersects the positive x-axis. You can do this with the “Intersect” tool by selecting the circle and the x-axis and naming the intersection point B.[br][/*][*]Measure the angle at the origin using the “Angle” tool. Select the points in the order B, O, A, and name this angle a. In the settings, keep the angle set to measure in degrees, so α will show the current value of a.[br][/*][*]Now add a dynamic text that shows the a. Choose the “Text” tool, and enter an expression, [b]"x = " + a[/b] ,so that the text updates automatically whenever a changes.[br][/*][*]Finally, create a Button and label it “Generate random angle!”. Open the button’s settings, go to the “Scripting” → “On Update” section, and type [code][/code][b]SetValue(k, RandomBetween(0, 360))[/b]. This script will assign new random angle for the a, between 0° and 360° every time the button is pressed.[br][/*][*]Press the button to test your construction. [/*][/list]