Answer the following questions regarding the idea of an onto function.
a. (i) State the definition of a surjective (onto) function.
b. (ii) Let A={1,2,3} and B={a,b,c}. A function f:A→B is given by f(1)=a,f(2)=b,f(3)=b. Determine whether f is onto. Give a clear reason for your answer.
c. (iii) By changing at most one value of f, construct a new function f~:A→B that is onto. Write the complete definition of f~ and justify that it is surjective.