Answer the following questions about relations and functions.
a. (i) Define a relation from a set A to a set B. Also state the additional condition required for a relation to be called a function.
b. (ii) Let A={1,2,3}, B={4,5} and R={(1,4),(1,5),(2,4)}. Using the definitions given in part (i), explain clearly whether R is a function from A to B.
c. (iii) For the relation R above, write its domain, co-domain and range as explicit sets.