1 x = undefined

     2 y = undefined

     3 z = undefined

     4 s = undefined

     5 u = undefined

     6 r = undefined

     7 t = undefined

     8 ReferenceError: "q" is not defined

     9 b = 10

    10 ReferenceError: "b" is not defined

    11 Value of 'a' inside the function 20

    12 Value of 'a' outside the function 10