How much weight can i lose in 3-4 weeks? Suggestions ASAP!!?

i am a female...age 24 and i currently workout 3x week for about an hour. i am increasing my workout to 5x a week now. i am really trying to drop these extra pounds ASAP! how much could i lose by the end of May beginning of June? like i do 30 mins of cardio every time and work my diff muscle groups. just give me a realistic opinion. ooo, i am also 5'8 and weigh about 175. thanx!