The line plot shows the number of hours students spent doing their math homework last week. A dot plot titled math homework time shows the number of hours spent doing homework. The data is as follows: 1 dot above 2, 2 dots above 2.5, 1 dot above 3, 2 dots above 4, 3 dots above 4.5, 1 dot above 5, and 2 dots above 5.5

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.