In combat, the typical soldier needs 3000 to 5000 calories a day to function. To keep the bulk of rations that he must carry to supply this down, the food in the rations concentrates on high density calories (fats - 9 cal/gm) and quickly available calories (carbohydrates - 4 cal/gm). Chocolate bars are good for this.
About 10% of the total calories intake.
There are so many types of foods out there, that it really depends on what the food is.
5000 calories
There is no such thing as "common foods". Foods are specific sometimes ot certain regions or areas, and there are so many foods out there. Please be more specific in your question, so WikiAnswers can provide you with the best possible answer.
Not enough to cancel out the calories of the orange. There are no "negative calorie" foods, with the exception of celery.
It all depends on what foods are in the meal and the serving size.
1500 calories a day eat natural healthy foods stay away from artificial packaged foods
This is a fun site. It lists over 60000 foods and their calorie counts. http://www.fitwatch.com/caloriecounter.html It is very simple to use and should help you with counting calories.
The United States Department of Agriculture has a "National Nutrient Database" which contains details of calories and nutrients in many different foods. http://www.nal.usda.gov/fnic/foodcomp/search/
anything they had!!! <><><> Many foods were rationed, as were shoes, tires, gasoline, flashlights and batteries, and clothing.
eat less. Burn more calories then you eat. Drink more water. cut out foods with a lot of sodium.
Because you eat fatty, greasy foods with too many calories to burn off and your body saves those calories as fat.