public Brick(int brickNum)
    {
        // brick 1 (easy)
        if (brickNum == 1)
        {
            setImage(brick1);
            hit = 1;
        }
        // brick 2 (easy)
        if (brickNum == 2)
        { 
            setImage(brick2);
            hit = 2;
        }
        // brick 3 (medium)
        if (brickNum == 3)
        {
            setImage(brick3);
            hit = 3;
        }     
        // brick 4 (medium)
        if (brickNum == 4)
        {
            setImage(brick4);
            hit = 4;
        }   
        // brick 5 (hard)
        if (brickNum == 5)
        {
            setImage(brick5);
            hit = 5;
        }   
        // brick 6 (hard)
        if (brickNum == 6)
        {
            setImage(brick6);
            hit = 6;
        }  
    }