25 points to whoever gets it right first plz help

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.

The area of a circle is equal to 1 dm². find the radius of the circle.

Why is it so easy to buy on impulse and overspend with a credit card? what could you do to counteract this tendency?