Which property of addition is shown below?

An automated water dispenser fills packets with one liter of water on average, with a standard deviation of 5 milliliter. the manual says that after a year of operation the dispenser should be tested to see if it needs recalibration. a year later a number of filled packets are set aside and measured separately. it is found that the average packet now contains about 0.995 liters. does the dispenser need calibration? explain your answer.

Sam claims that cos x =sin y if x and y are congruent angels. is sam correct ?

Antonia and carla have an equivalant percentage of green marbles in their bags of marbles. antonia has 4 green marbles and 16 total matbles. if carla has 10 green marbles , how many total marbles does carla have