You can use the following keystrokes in the sketch applet below:

x	Cut	g	Group
c	Copy	u	Ungroup
v	Paste	o	Grid toggle

To draw an arc, first click and hold the mouse button on the center of the radius of your arc, then drag (with the button down) until you have the correct radius and starting point of your arc. Now release the mouse button, then click and drag again to set the ending point of the arc.

Use the arrow icon to manipulate shapes after you have drawn them.

To send your sketch, click on the envelope icon. You can then enter your address to receive a copy of the sketch and attach any comments.