1. Which of the following are valid array declarations? If it is not valid write a valid statement. (2 pts)

a. char[26] charArray = new char[26]; b. int[10] words = new int[]; c. char[] charArray = "Computer Science"; d. double[] nums = {3.5, 35.1, 32.0};

2. Write the output of the following code: (2 pts)

public class Hw7 { public static void main(String[] args) 

 { int[] x = new int[10]; for (int i = 0; i < x.length; i++) 

 { x[i] = i + 2; } } } System.out.println(x[i]); 

3. Write a method that takes an array of Strings as a parameter and the number of elements currently stored in the array, and returns a single String that is the concatenation of all Strings in the array. (3pts)