Что выведет: synchronized и AtomicInteger

import java.util.concurrent.atomic.AtomicInteger;

public class Main {
    private static int plain = 0;
    private static final Object lock = new Object();

    public static void main(String[] args) throws InterruptedException {
        AtomicInteger atomic = new AtomicInteger();
        Thread[] ts = new Thread[4];
        for (int i = 0; i < ts.length; i++) {
            ts[i] = new Thread(() -> {
                for (int j = 0; j < 10_000; j++) {
                    synchronized (lock) { plain++; }
                    atomic.incrementAndGet();
                }
            });
            ts[i].start();
        }
        for (Thread t : ts) t.join();
        System.out.println(plain);
        System.out.println(atomic.get());
        System.out.println(atomic.getAndAdd(5) + " " + atomic.addAndGet(5));
    }
}