You are checking the results of a phone app that counts calories. When someone eats, it is recorded as positive calories. When someone exercises, it is recorded as negative calories. What is the number of net calories for a person with the following record?
Description Calories
Bike, 30 min
−270
Breakfast
560
Lunch
770
Walk, 45 min
−80
Dinner
990
Tennis, 30 min
−130