You can use the Draw tool to draw straight lines and curved lines. You can set the width of the line and whether the line is antialiased in the Tool Options window.
As an exercise, and to get some hands-on experience with the Draw tool, you can add an arrow to the bull's-eye from the previous exercise.
Open the bull's-eye file that you saved, and then follow these steps:
Set the foreground color to a shade of blue or some color other than the black and red you used for the rings of the bull's-eye.
Select the Draw tool and, in the Tool Options window, set the Line Type to Single Line and the Width to 12, and place a check mark in the Antialias check box. Make sure the Create as Vector option is unchecked. ...