I want to know if they asked reliable questions like 'how many friends do you have', or ones which people are prone to lie about like 'how much time do you spen

I want to know if they asked reliable questions like 'how many friends do you have', or ones which people are prone to lie about like 'how much time do you spend on facebook per week?' Maybe the 'NFC' people are just more willing to admit how much time they really waste on FB.