Question $3(20\mathrm{.}0$ marks$)$ Your lecturer is a funny guy; given an unsorted list of integer numbers of n elements, and to find the sum of all the numbers in the list, he will use the following algorithms. function Sum$($A$,$ left, right$)$ if left $>$ right: return $0$ else if left $=$ right: return A$[$left$]$ mid $=$ floor$(($left$+$right$)/2)$ Isum $=$ Sum$($A$,$ left, mid$)$ rsum $=$ Sum$($A$,$ mid$+1,$ right$)$ return Isum $+$ rsum $+$ A$[$mid$)$ function myMethod$($A$,$ N$)$ B $=$ new Array of length $1$ B$[0]=$ Sum$($A$,0,$ N$-1)$ return B $($a$)$ Analyse the asymptotic run$-$time complexity of the method myMethods. Give the worst$-$case and the best$-$case running time in terms of o notation. Justify your answer. $(15\mathrm{.}0$ marks$)$