Xmin=0
Xmax=50
Xdiv=5
Ymin=0
Ymax=1.25
Ydiv=0.25
~
plot X/(10+20)
plot X/(10+X)
plot X/(10+0.13*X^2)
plot X/(10+X+0.13*X^2)
~
plot X/(4+20)
plot X/(4+X)
plot X/(4+0.13*X^2)
plot X/(4+X+0.13*X^2)