Assume that an ArrayList of integers named a has been declared and initialized. Write a single statement that assigns a new value to the first element of the ArrayList. The new value should be equal to twice the value stored in the last element of the ArrayList.

Following are the code to this question:

a[0] = a[a. length-1] * 2; / /assign value in the first element in array

Explanation:

In the given question, it is declared, that an array list "a" is declared, that contains only integer number, in which we assign a number in the array list first element so, the code to this question can describe as follows:

As we known array indexing always starts with 0. so, in the above code an array "a[0]" is used, which uses "length-1" to calculate the total length of the array and then subtract from 1. After calculating array length we multiply the value by 2, in this, the new value is twice to the last value, which is stored in the array.