In what year did 'Saturday Night Live' premiere?

In what year did 'Welcome Back, Kotter' premiere? Where is 'Welcome Back, Kotter' set? Who created 'Welcome Back, Kotter'? On which network did 'Saturday Night Live' originally air? Where is 'Saturday Night Live' set? In what year did 'Wheel of Fortune' premiere? Who created 'Wheel of Fortune'? On which network did 'Laverne & Shirley' originally air?