Polar definitions: Sec=90°-(6a)°, Min=90°-(a/10)°, Hour=90°-(a/120)°
NOTE 1: when using polar coordinates a semicolon is needed
NOTE 2: “Alt-o” (letter O, not number 0) gives degree symbol
Vectors are used for clock hands.
-from wikimedia commons: the clock face background,
and set at Layer=0; other graphics are at Layer=1
-Animation speed = 0.00023148 to move second hand accurately
-ref: Malin Christersson-http://www.malinc.se/math/geogebra/slideren.php
