How long will it take me to lose 75 lbs...im on a 1000 calorie diet a day and i exercise for a about a hour a day?

Be patient, patient: There is no exact answer for you, and 75# is alot to lose, so be patient. Everyone metabolizes foods differently, and depneding on the exercise you do, it may be a slower loss than you would like, ...But be patient, as a good weight loss program/regimen, coupled with an approved exercise program will eventually reap the benefits you desire. Good luck.