question: public void drawStdDevLine ( Graphics2D g2d , Long stdDevVal , long yMaxMark , Color color ) { float stdDevPerc = stdDevVal / ( float ) yMaxMark ; g2d . setColor ( color ) ; int yPosOfLine = this . graphBottom - Math . round ( this . graphHeight * stdDevPerc ) ; g2d . drawLine ( this . graphLeft , yPosOfLine , this . graphRight , yPosOfLine ) ; }
target:  Used to draw the low and high standard devition lines on the line graph