Question 4 [15 Marks] (Long Answer Question) File Upload Required (a) Given that f(t) = - to + 4t + 5 t 2 + 3t + 2 , explain whether f(t) is a proper rational function or improper rational function (Word limit 25). (b) Factorise t2 + 3t + 2. (c) Given that B f (t) = Q(t ) + + + 1 + t+2' A and Q(t) is a polynomial of degree zero, and A and B are constants, find Q(t) and the values of A and B. (d) Show that 1 . "s(t ) at = 1 + In(? )