Answer:
a) 0.0374 , b) 0.6500 , c) 0.3500 
Explanation:
Pr (Both consider celebrities role models) = (213/1100) x (212/1099) 
= 0.0374 
Pr (None consider celebrities role models) = (887/1100) x (886/1099) 
= 0.6500 
Pr (atleast one consider celebrities role models) = 1 - Pr (None consider role models) 
1 - 0.6500 = 0.3500