[userrc651]

Ok, I'll start with the toString method since that's where it appears you left off.

public String toString()
{
String output;
if (hours > 12)
      output = hours%12 + ":" + minutes + ":" + seconds +"  PM";
else   output = hours%12 + ":" + minutes + ":" + seconds + "  AM";
return output;
}

And for the subtract method...

public static Duration Subtract(Time t1, Time t2)
{
int hr_dif, min_dif, sec_dif;

if t1.getHours() < t2.getHours)
//throw exception I'll leave this up to you.

else
{
hr_dif = t1.getHours() - t2.getHours();
min_dif = t1.getMinutes - t2.getMinutes();
sec_dif = t1.getSeconds() - t2.getSeconds();
}

//create new Duration object with the difference in time
Duration time_dif = new Duration(hr_dif, min_dif, sec_dif);

return time_dif;
}

Give that a shot, there may be some syntax errors (I did it rather quickly), let me know how it turns out for you.

EDIT: The subtract method is incorrect for a number of reasons (negative seconds) and (what if seconds/minutes > 60). I'll leave this part up to you. ;-)

2nd EDIT: I'm retarded... the Duration class already handles minutes/seconds > 60... so really you have two options. Either use the absolute value function or double negate them. Ex. (if min < 0) min = -min.