Radio Button

Hi Group,

Have a req:

Have 2 radio buttons on selection screen and two parameters input fields. When first radio button is selected have I have disable the 2 parameter input fields, and when second radio button is selected I have to enable the 2 parameter input fields. By default first radio button is selected, so there itself I have to make that 2 parameter input fields inactive, when second radio button is selected I have to make the 2 input fields as active.

Can you plz help.