Only need help with 5, 19, and 21 please.

19-24 Explain why the function is discontinuous at the given number a. Sketch the graph of the function. 19. f (x) = 0 =-2 x +2x+3 ifx=-1 21. f(x) = 7= -1 if x > - 15-6 The graph of a function f is given. (a) At what numbers a does lim -. f(x) not exist? (b) At what numbers a is f not continuous? (c) At what numbers a does lim .-a f(x) exist but f is not continuous at a? 5. VA 6. VA O