I only need 3-5, thanks !

2.1 ArrayStacks Recall that an ArrayStack stores n elements in a backing array a at locatios0. a[n-1]: public class ArrayStack extends AbstractList Tli a int n; 1. 2. Describe the implementation and running times of the operations get(i) and set(i,x) in an ArrayStack. Recall that the length of the backing array a in an ArrayStack doubles when we try to add an element and n+1> a.length. Explain, in general termswhy we choose to double rather than just add 1 or a constant. 3. Recall that, immediately after an ArrayStack is resized it has a.length 2*n If we are currently about to grow the backing array a, what can you say about the number of add() and remove() operations since the last time the ArrayStack was resized? a. b. Recall that we shrink the back array a when 3*n