Are the specified lines of code good or bad uses of whitespace?

import java.util.Scanner;

public class WhitespaceGoodAndBad $\{$

public static void main$($String$[]$ args$)\{$

Scanner scnr $=$ new Scanner$($System$.$in$)$;

int userAge;

int currentDecade;

int nextDecade;

int nextMilestone;

System.out.println$("$Enter your age: $")$;

userAge $=$ scnr$.$nextInt$()$;

currentDecade$=$userAge$/10$;

nextDecade $=$ currentDecade $+1$;

nextMilestone $=$ nextDecade $*10$;

System.out.println$("$Next big birthday is at $"+$ nextMilestone$)$;

$\}$

$\}$

$1)$

int nextDecade;

$2)$

currentDecade$=$userAge$/10$;

$3)$

nextDecade $=$ currentDecade $+1$;

$4)$

nextMilestone $=$ nextDecade $*10$;