Join Lists or arrays

Questions
1

Hi Guys I want to join these list as example

a ={1,2,4,5};
b={5,5,5,5};
c= should be {a,b} i want
c= {{1,5},{2,5},{4,5},{5,5}};

Thank you.

2

a = {1, 2, 4, 5}; b = {5, 5, 5, 5};
c = Transpose[{a, b}]

(*{{1, 5}, {2, 5}, {4, 5}, {5, 5}}*)

Regards M.I.