What is science and what are some examples of science 2 paragraphs.

Which is an equation for the nth terms of the sequence 12,15,18,21

The equation respenting the left table is

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.