clear()
setBackground(white)
invisible()
setSpeed(fast)
setPenThickness(3)
setPenColor(black)
circle(100)
circle(95)
circle(90)
circle(85)
circle(80)
circle(75)
circle(70)
circle(65)
circle(60)
circle(55)
circle(50)
circle(45)
circle(40)
circle(35)
circle(30)
circle(25)
circle(20)
circle(15)
circle(10)
circle(5)