@Test
public void testPutIn() {

    Liquid content = new Liquid(100, 350, new Color(0x003000));
    MixTankSimulation tank = new MixTankSimulation(1000, content, pipe);
    LinkedList<Liquid> input = new LinkedList<>();
    input.add(new Liquid(100, 375, new Color(0x000000)));
    input.add(new Liquid(100, 400, new Color(0x300000)));
    tank.putIn(input);
    assertEquals(new Liquid(300, 375, new Color(0x101000)), tank.getLiquid());
}