Answer:
import java.util.Scanner;
public class numm3 {
    public static void main (String [] args) {
        Scanner scnr = new Scanner(System.in);
        final int NUM_POINTS = 4;
        int[] dataPoints = new int[NUM_POINTS];
        int controlValue;
        int i;
        System.out.println("Enter the control Variable");
        controlValue = scnr.nextInt();
        System.out.println("enter elements for the array");
        for (i = 0; i < dataPoints.length; ++i) {
            dataPoints[i] = scnr.nextInt();
        }
        for (i = 0; i < dataPoints.length; ++i) {
            System.out.print(dataPoints[i] + " ");
        }
        System.out.println();
        //Doubling elements Less than Control Variable
        for (i = 0; i < dataPoints.length; ++i) {
            if (dataPoints[i]<controlValue){
                dataPoints[i] = dataPoints[i]*2;
            }
            System.out.print(dataPoints[i] + " ");
        }
        System.out.println(); } }
Explanation:
See the additional code to accomplish the task in bold
The trick is using an if statement inside of a for loop that checks the condition  (dataPoints[i]<controlValue) If true, it multiplies the element by 2