RadioButton with Dropdown

Question

HI 

I am having a radio button(rbn1) and 3 drop down lists(country,state,city) in my form.

if i select my radio button then 

country drop down should be enabled and state and city drop down should be disabled the country drop down list items ( India,USA)

Now if i select the India from list item..then state Drop down list should be enabled 

and city drop down should be disabled 

Now if i select the USA from list item then city Drop down list should be enabled and state drop down should be disabled.

Is it possible?