Which functions in Exercise 10 are onto?

Solution:Step 1In this problem we need to enquire if the given functions are onto or not.Step 2A function is onto if and only if for every element in codomain of the function there is at least one element in domain which corresponds to that element in codomain. Using this definition we enquire the given functions as followsa) For every element in codomain {a,b,c,d},...